### Run Jupyter Notebooks for Tutorials

Source: https://github.com/stac-utils/pystac/blob/main/README.md

Start a Jupyter notebook server in the 'docs' directory to access and run quickstart and tutorial notebooks.

```shell
jupyter notebook --ip 0.0.0.0 --port 8888 --notebook-dir=docs
```

--------------------------------

### Install PySTAC from PyPI

Source: https://github.com/stac-utils/pystac/blob/main/README.md

Install the core PySTAC library using pip. This is the recommended installation method.

```shell
python -m pip install pystac
```

--------------------------------

### Install PySTAC Locally

Source: https://github.com/stac-utils/pystac/blob/main/docs/contributing.md

Clone the PySTAC repository and install it locally using uv. Ensure you activate the virtual environment after installation.

```bash
git clone git@github.com:your_user_name/pystac.git
cd pystac
uv sync
source .venv/bin/activate
```

--------------------------------

### Install PySTAC from Source

Source: https://github.com/stac-utils/pystac/blob/main/README.md

Clone the PySTAC repository and install it locally from the source code.

```shell
git clone https://github.com/stac-utils/pystac.git
cd pystac
python -m pip install .
```

--------------------------------

### Install PySTAC from Source

Source: https://github.com/stac-utils/pystac/blob/main/docs/installation.md

Install PySTAC directly from its GitHub repository. This is useful for development or when needing the latest unreleased code.

```bash
pip install git+https://github.com/stac-utils/pystac.git
```

--------------------------------

### Link Extension Example

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/link.md

This example demonstrates how to set an extension field on a link. Ensure the relevant extension is loaded.

```python
link.ext.file.size = 8675309
```

--------------------------------

### Install PySTAC and Dependencies

Source: https://github.com/stac-utils/pystac/blob/main/docs/tutorials/how-to-create-stac-catalogs.ipynb

Installs the pystac library along with boto3, rasterio, and shapely. Use this command in your environment before running the tutorial.

```python
%pip install boto3 rasterio shapely pystac --quiet
```

--------------------------------

### Install PySTAC with orjson Support

Source: https://github.com/stac-utils/pystac/blob/main/README.md

Install PySTAC with optional orjson support for faster JSON serialization/deserialization.

```shell
python -m pip install 'pystac[orjson]'
```

--------------------------------

### Install PySTAC from PyPI

Source: https://github.com/stac-utils/pystac/blob/main/docs/installation.md

Use this command to install the latest stable version of PySTAC from the Python Package Index.

```bash
pip install pystac
```

--------------------------------

### Install PySTAC and Planetary Computer

Source: https://github.com/stac-utils/pystac/blob/main/docs/tutorials/creating-a-landsat-stac.ipynb

Installs PySTAC with validation extras and the Planetary Computer package. Requires Jupyter to be installed locally.

```bash
pip install 'pystac[validation]' planetary-computer
```

--------------------------------

### Install PySTAC with Validation Support

Source: https://github.com/stac-utils/pystac/blob/main/README.md

Install PySTAC with optional validation features, which requires the jsonschema library.

```shell
python -m pip install 'pystac[validation]'
```

--------------------------------

### Install pytest-pystac

Source: https://github.com/stac-utils/pystac/blob/main/pytest-pystac/README.md

Install the pytest-pystac plugin using pip.

```shell
pip install pytest-pystac
```

--------------------------------

### Install PySTAC with Jinja2 Support

Source: https://github.com/stac-utils/pystac/blob/main/README.md

Install PySTAC with optional Jinja2 support for enabling pretty display of pystac objects in Jupyter notebooks.

```shell
python -m pip install 'pystac[jinja2]'
```

--------------------------------

### Install PySTAC with urllib3 Support

Source: https://github.com/stac-utils/pystac/blob/main/README.md

Install PySTAC with optional urllib3 support for retrying network requests, useful for custom RetryStacIO or non-ASCII URLs.

```shell
python -m pip install 'pystac[urllib3]'
```

--------------------------------

### Install PySTAC from conda-forge

Source: https://github.com/stac-utils/pystac/blob/main/docs/installation.md

Install PySTAC using the conda package manager from the conda-forge channel.

```bash
conda install -c conda-forge pystac
```

--------------------------------

### Install Pre-commit Hooks

Source: https://github.com/stac-utils/pystac/blob/main/docs/contributing.md

Install Git pre-commit hooks to automatically run linters and formatters on staged code before committing. Use --overwrite to ensure the latest configuration is applied.

```bash
pre-commit install --overwrite
```

--------------------------------

### Install PySTAC with urllib3 Extras

Source: https://github.com/stac-utils/pystac/blob/main/docs/installation.md

Install PySTAC with the 'urllib3' extra, which is used in RetryStacIO for enhanced network request handling. This adds the 'urllib3' dependency.

```bash
pip install pystac[urllib3]
```

--------------------------------

### Install PySTAC with Jinja2 Extras

Source: https://github.com/stac-utils/pystac/blob/main/docs/installation.md

Install PySTAC with the 'jinja2' extra to enable pretty representations of PySTAC objects in Jupyter notebooks. This adds the 'jinja2' dependency.

```bash
pip install pystac[jinja2]
```

--------------------------------

### Install Specific PySTAC Version for STAC v0.9.x

Source: https://github.com/stac-utils/pystac/blob/main/docs/installation.md

Install a specific version of PySTAC (e.g., 0.4.0) to ensure compatibility with older STAC specification versions like v0.9.x.

```bash
pip install pystac==0.4.0
```

--------------------------------

### Accessing Collection Extension Properties

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/collection.md

Use the `.ext` accessor to get extension classes for a collection. This example shows how to access the xarray extension.

```python
print(collection.ext.xarray)
```

--------------------------------

### Get All Items Recursively

Source: https://github.com/stac-utils/pystac/blob/main/docs/tutorials/pystac-introduction.ipynb

Retrieve all STAC Item objects located anywhere within the STAC tree, starting from the current object. This traverses all nested catalogs and collections.

```python
# get all items anywhere below this catalog on the STAC tree
list(cat.get_items(recursive=True))
```

--------------------------------

### Define Collection Extent

Source: https://github.com/stac-utils/pystac/blob/main/docs/tutorials/creating-a-landsat-stac.ipynb

Set the spatial and temporal extent for the STAC Collection. This example defines a global spatial extent and an open-ended temporal interval starting from a specific date.

```python
spatial_extent = pystac.SpatialExtent([[-180.0, -90.0, 180.0, 90.0]])
temporal_extent = pystac.TemporalExtent([[datetime(2013, 6, 1), None]])
collection_extent = pystac.Extent(spatial_extent, temporal_extent)
```

--------------------------------

### Example Benchmark Comparison Output

Source: https://github.com/stac-utils/pystac/blob/main/docs/contributing.md

Illustrates a typical output format for benchmark comparisons between different versions, showing performance metrics and ratios.

```text
      before           after         ratio
    [eee06027]       [579c071b]
    <v1.0.0^0>       <v1.6.1^0>
-        533±20μs         416±10μs     0.78  collection.CollectionBench.time_collection_from_file [gadomski/virtualenv-py3.10-orjson]
-         329±8μs         235±10μs     0.72  collection.CollectionBench.time_collection_from_dict [gadomski/virtualenv-py3.10-orjson]
-        332±10μs          231±4μs     0.70  collection.CollectionBench.time_collection_from_dict [gadomski/virtualenv-py3.10]
-         174±4μs          106±2μs     0.61  item.ItemBench.time_item_from_dict [gadomski/virtualenv-py3.10]
-         174±4μs          106±2μs     0.61  item.ItemBench.time_item_from_dict [gadomski/virtualenv-py3.10-orjson]
    before           after         ratio
    [eee06027]       [579c071b]
    <v1.0.0^0>       <v1.6.1^0>
+        87.1±3μs          124±5μs     1.42  catalog.CatalogBench.time_catalog_from_dict [gadomski/virtualenv-py3.10]
+        87.1±4μs          122±5μs     1.40  catalog.CatalogBench.time_catalog_from_dict [gadomski/virtualenv-py3.10-orjson]
```

--------------------------------

### Display Collection Initialization Help

Source: https://github.com/stac-utils/pystac/blob/main/docs/tutorials/creating-a-landsat-stac.ipynb

Shows the signature for the pystac.Collection constructor, detailing the required and optional parameters for creating a Collection object.

```python
help(pystac.Collection.__init__)
```

--------------------------------

### Display pystac.Item.__init__ signature

Source: https://github.com/stac-utils/pystac/blob/main/docs/tutorials/creating-a-landsat-stac.ipynb

Use the `help` method to view the signature of the `pystac.Item.__init__` method for understanding required arguments.

```python
help(pystac.Item.__init__)
```

--------------------------------

### Get Projection Extension Schema URI

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/projection.md

Gets the schema URI associated with the Projection Extension.

```python
uri = ProjectionExtension.get_schema_uri()
```

--------------------------------

### Initialize a pystac Collection

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/pystac.md

Create a new STAC Collection with essential metadata like ID, description, and extent. Optional parameters allow for title, extensions, license, keywords, providers, summaries, assets, and layout strategy.

```python
pystac.Collection(id='my-collection', description='A detailed description of my collection.', extent=pystac.utils.make_simple_extent([-10, -20], [10, 20]), title='My Collection Title', license='CC-BY-4.0', keywords=['example', 'data'], providers=[pystac.Provider(name='Provider Name', roles=['host'], url='https://example.com')], summaries={'gsd': {'minimum': 10, 'maximum': 100}}, assets={'thumbnail': pystac.Asset(href='https://example.com/thumbnail.jpg', media_type='image/jpeg', title='Thumbnail')}, strategy=pystac.layout.BestPracticesLayoutStrategy())
```

--------------------------------

### Inspect pystac.Catalog Initialization

Source: https://github.com/stac-utils/pystac/blob/main/docs/tutorials/how-to-create-stac-catalogs.ipynb

Displays the initialization signature and docstring for the pystac.Catalog class to understand its required and optional parameters.

```python
?pystac.Catalog
```

--------------------------------

### Initialize New Catalog

Source: https://github.com/stac-utils/pystac/blob/main/docs/tutorials/pystac-introduction.ipynb

Create a new STAC Catalog object with a specified ID and description. By default, a new catalog is set as its own root.

```python
# create a Catalog object with JSON
mycat = pystac.Catalog(id="mycat", description="My shiny new STAC catalog")
```

--------------------------------

### Get Projection Extension Schema URIs

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/projection.md

Gets a list of all schema URIs associated with the Projection Extension.

```python
uris = ProjectionExtension.get_schema_uris()
```

--------------------------------

### Create a STAC Catalog

Source: https://github.com/stac-utils/pystac/blob/main/docs/tutorials/how-to-create-stac-catalogs.ipynb

Instantiates a STAC Catalog with an ID and description. Requires pystac.

```python
catalog = pystac.Catalog(id="spacenet5", description="Spacenet 5 Data (Test)")
```

--------------------------------

### Inspect pystac.Item Initialization

Source: https://github.com/stac-utils/pystac/blob/main/docs/tutorials/how-to-create-stac-catalogs.ipynb

Displays the initialization signature and docstring for the pystac.Item class, detailing the parameters needed to create a STAC Item.

```python
?pystac.Item
```

--------------------------------

### Run Development Benchmarks

Source: https://github.com/stac-utils/pystac/blob/main/docs/contributing.md

Executes a shortened version of the benchmark suite for faster iteration during development. Ensure benchmark dependencies are installed.

```bash
asv dev
```

--------------------------------

### Create Temporary Directory for Saving

Source: https://github.com/stac-utils/pystac/blob/main/docs/quickstart.ipynb

Prepare a temporary directory on the local filesystem to store the normalized STAC catalog.

```python
# Create a temporary directory
tmp_dir = tempfile.mkdtemp()
```

--------------------------------

### Get current UTC time

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/utils.md

Use `now_in_utc` to get a `datetime` object representing the current time, with the UTC timezone explicitly set.

```python
from pystac.utils import now_in_utc

print(now_in_utc())
```

--------------------------------

### Get or Set Item Projection Code

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/projection.md

Gets or sets the projection code of the datasource, such as 'EPSG:4326'. This replaces the older 'proj:epsg' property.

```python
code = item.ext.proj.code
```

```python
item.ext.proj.code = 'EPSG:4326'
```

--------------------------------

### Render.apply

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/render.md

Sets the properties for a new Render, defining how assets should be rendered.

```APIDOC
## Render.apply

### Description
Set the properties for a new Render. This method defines how assets are used and visualized in a rendered output.

### Method
`apply`

### Parameters
* **assets** (list[str]) - Required - List of asset keys referencing the assets that are used to make the rendering.
* **title** (str | None) - Optional - Title of the rendering.
* **rescale** (list[list[float]] | None) - Optional - A list of min/max value pairs to rescale each asset by, e.g. `[[0, 5000], [0, 7000], [0, 9000]]`. If not provided, the assets will not be rescaled.
* **nodata** (float | str | None) - Optional - Nodata value.
* **colormap_name** (str | None) - Optional - Name of color map to apply to the render. See: [https://matplotlib.org/stable/gallery/color/colormap_reference.html](https://matplotlib.org/stable/gallery/color/colormap_reference.html)
* **colormap** (dict[str, Any] | None) - Optional - A dictionary containing a custom colormap definition. See: [https://developmentseed.org/titiler/advanced/rendering/#custom-colormaps](https://developmentseed.org/titiler/advanced/rendering/#custom-colormaps)
* **color_formula** (str | None) - Optional - A string containing a color formula to apply color corrections to images. Useful for reducing artifacts like atmospheric haze, dark shadows, or muted colors. See: [https://developmentseed.org/titiler/advanced/rendering/#color-formula](https://developmentseed.org/titiler/advanced/rendering/#color-formula)
* **resampling** (str | None) - Optional - Resampling algorithm to apply to the referenced assets. See GDAL resampling algorithm for some examples. [https://gdal.org/en/latest/programs/gdalwarp.html#cmdoption-gdalwarp-r](https://gdal.org/en/latest/programs/gdalwarp.html#cmdoption-gdalwarp-r)
* **expression** (str | None) - Optional - Band arithmetic formula to apply to the referenced assets.
* **minmax_zoom** (list[int] | None) - Optional - Zoom level range applicable for the visualization, e.g. `[2, 18]`.
```

--------------------------------

### Get Latest Version Link

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/version.md

Access the `latest` property of a VersionExtension instance to get or set the Link to the STAC object representing the most recent version.

```python
>>> latest_link = version_ext.latest
```

--------------------------------

### Create a Render object

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/render.md

Use the `create` class method to instantiate a `Render` object. This method takes a list of asset keys and various optional parameters to define how the assets should be rendered.

```python
Render.create(assets=["asset1.tif", "asset2.tif"], title="My Render", rescale=[[0, 10000]], nodata=-9999, colormap_name="viridis", color_formula="Gamma(1.5)", resampling="bilinear", expression="B1/B2", minmax_zoom=[2, 16])
```

--------------------------------

### Read Data using STAC Reference File

Source: https://github.com/stac-utils/pystac/blob/main/docs/tutorials/how-to-read-data-from-stac.ipynb

This example shows how to open a dataset using a STAC asset that points to a reference file (e.g., for kerchunk). It signs the asset and uses the `patch_url` argument in `xarray.open_dataset`.

```python
cmip6_collection = pystac.Collection.from_file(
    "https://planetarycomputer.microsoft.com/api/stac/v1/collections/nasa-nex-gddp-cmip6"
)
cmip6_asset = cmip6_collection.assets["ACCESS-CM2.historical"]
cmip6_asset_signed = planetary_computer.sign(cmip6_asset)

ds = xr.open_dataset(cmip6_asset_signed, chunks={}, patch_url=planetary_computer.sign)
```

--------------------------------

### Get or Set Item Shape

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/projection.md

Gets or sets the number of pixels in the Y and X directions for the default grid. This is used for assets that don't have an overriding shape.

```python
shape = item.ext.proj.shape
```

```python
item.ext.proj.shape = [y_pixels, x_pixels]
```

--------------------------------

### Get Datacube Extension for an Item

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/datacube.md

Use DatacubeExtension.ext() to get the Datacube Extension for an Item. This is the recommended way to extend STAC objects with Datacube properties.

```python
>>> item: pystac.Item = ...
>>> dc_ext = DatacubeExtension.ext(item)
```

--------------------------------

### Example Asset Metadata

Source: https://github.com/stac-utils/pystac/blob/main/docs/tutorials/creating-a-landsat-stac.ipynb

Demonstrates the structure for defining an asset's type, title, and detailed classification bitfields.

```json
{
  "type": "image/tiff; application=geotiff; profile=cloud-optimized",
  "title": "Aerosol Quality Assessment Band",
  "classification:bitfields": [
    {
      "offset": 0,
      "length": 1,
      "classes": [
        {
          "value": 0,
          "name": "not_fill",
          "description": "Pixel is not fill"
        },
        {
          "value": 1,
          "name": "fill",
          "description": "Pixel is fill"
        }
      ],
      "description": "Image or fill data",
      "name": "fill"
    },
    {
      "offset": 1,
      "length": 1,
      "classes": [
        {
          "value": 0,
          "name": "not_valid",
          "description": "Pixel retrieval is not valid"
        },
        {
          "value": 1,
          "name": "valid",
          "description": "Pixel retrieval is valid"
        }
      ],
      "description": "Valid aerosol retrieval",
      "name": "retrieval"
    },
    {
      "offset": 2,
      "length": 1,
      "classes": [
        {
          "value": 0,
          "name": "not_water",
          "description": "Pixel is not water"
        },
        {
          "value": 1,
          "name": "water",
          "description": "Pixel is water"
        }
      ],
      "description": "Water mask",
      "name": "water"
    },
    {
      "offset": 5,
      "length": 1,
      "classes": [
        {
          "value": 0,
          "name": "not_interpolated",
          "description": "Pixel is not interpolated"
        },
        {
          "value": 1,
          "name": "interpolated",
          "description": "Pixel is interpolated"
        }
      ],
      "description": "Aerosol interpolation",
      "name": "interpolated"
    },
    {
      "offset": 6,
      "length": 2,
      "classes": [
        {
          "value": 0,
          "name": "climatology",
          "description": "No aerosol correction applied"
        },
        {
          "value": 1,
          "name": "low",
          "description": "Low aerosol level"
        },
        {
          "value": 2,
          "name": "medium",
          "description": "Medium aerosol level"
        },
        {
          "value": 3,
          "name": "high",
          "description": "High aerosol level"
        }
      ],
      "description": "Aerosol level",
      "name": "level"
    }
  ]
}
```

--------------------------------

### Import Pystac

Source: https://github.com/stac-utils/pystac/blob/main/docs/tutorials/pystac-introduction.ipynb

Import the pystac library to begin working with STAC objects.

```python
import pystac
```

--------------------------------

### Get or Set Item EPSG Code

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/projection.md

Gets or sets the EPSG code of the datasource. Set to None if no valid EPSG code exists or if the data does not have a CRS.

```python
epsg_code = item.ext.proj.epsg
```

```python
item.ext.proj.epsg = 4326
```

--------------------------------

### Python Import Style Guide

Source: https://github.com/stac-utils/pystac/blob/main/docs/contributing.md

Demonstrates the preferred Python import style for consistency. Avoid importing modules with aliases unless necessary for type checking.

```python
# DO
from datetime import datetime

# DON'T
import datetime
import datetime as dt
```

--------------------------------

### Get or Set Item Bounding Box

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/projection.md

Gets or sets the bounding box of the assets represented by this item. The format (4 or 6 coordinates) depends on the CRS.

```python
bbox = item.ext.proj.bbox
```

```python
item.ext.proj.bbox = [west, south, east, north]
```

--------------------------------

### Get or Set Item PROJJSON

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/projection.md

Gets or sets the PROJJSON string representing the Coordinate Reference System (CRS). This is used for proj:geometry and proj:bbox fields.

```python
projjson_data = item.ext.proj.projjson
```

```python
item.ext.proj.projjson = { ... }
```

--------------------------------

### Read Example Catalog

Source: https://github.com/stac-utils/pystac/blob/main/docs/quickstart.ipynb

Read a STAC catalog from a local file path using Catalog.from_file. This is useful for loading an existing catalog structure.

```python
root_catalog = Catalog.from_file("./example-catalog/catalog.json")
print(f"ID: {root_catalog.id}")
print(f"Title: {root_catalog.title or 'N/A'}")
print(f"Description: {root_catalog.description or 'N/A'}")
```

--------------------------------

### Get or Set Item Geometry

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/projection.md

Gets or sets a Polygon GeoJSON dict representing the footprint of this item. The geometry is based on the CRS defined in code, projjson, or wkt2 fields.

```python
geometry = item.ext.proj.geometry
```

```python
item.ext.proj.geometry = { ... }
```

--------------------------------

### Initialize a pystac Catalog

Source: https://github.com/stac-utils/pystac/blob/main/docs/tutorials/pystac-spacenet-tutorial.ipynb

Creates an in-memory pystac Catalog object with a specified ID and description. This serves as the root for organizing STAC collections and items.

```python
spacenet = pystac.Catalog(id="spacenet", description="SpaceNet 2 STAC")
```

--------------------------------

### Create a STAC Catalog Instance

Source: https://github.com/stac-utils/pystac/blob/main/docs/tutorials/how-to-create-stac-catalogs.ipynb

Initializes a new STAC Catalog with a unique ID and a descriptive string. The HREF is not set at this stage.

```python
catalog = pystac.Catalog(id="test-catalog", description="Tutorial catalog.")
```

--------------------------------

### Run Continuous Benchmarks

Source: https://github.com/stac-utils/pystac/blob/main/docs/contributing.md

Compares the current HEAD with the main branch to report performance improvements or regressions. Requires benchmark dependencies to be installed.

```bash
asv continuous --split -e --interleave-rounds --factor 1.25 main HEAD
```

--------------------------------

### Get EO Extension Summaries for Collection

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/eo.md

Use the summaries class method to get the extended summaries object for a given STAC Collection, enabling access to EO-specific summary statistics.

```python
>>> summaries = EOExtension.summaries(collection)
```

--------------------------------

### strategy

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/pystac.md

Gets or sets the HrefLayoutStrategy for this object.

```APIDOC
## property strategy *: [HrefLayoutStrategy](layout.md#pystac.layout.HrefLayoutStrategy) | None*

### Description
Gets or sets the HrefLayoutStrategy for this object.
```

--------------------------------

### ItemAssetDefinition.description

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/item_assets.md

Gets or sets a description of the Asset.

```APIDOC
## ItemAssetDefinition.description

### Description
Gets or sets a description of the Asset providing additional details, such as how it was processed or created. [CommonMark 0.29](http://commonmark.org/) syntax MAY be used for rich text representation.

### Property
`description: str | None`
```

--------------------------------

### code

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/projection.md

Get or set the code of the datasource.

```APIDOC
## code

### Description
Get or set the code of the datasource.

Added in version 2.0.0 of this extension replacing “proj:epsg”.

Projection codes are identified by a string. The [proj](https://proj.org/) library defines projections using “authority:code”, e.g., “EPSG:4326” or “IAU_2015:30100”. Different projection authorities may define different string formats.

### Type
str | None
```

--------------------------------

### Inspect pystac Collection Initialization

Source: https://github.com/stac-utils/pystac/blob/main/docs/tutorials/how-to-create-stac-catalogs.ipynb

Displays the initialization signature and docstring for the pystac.Collection class. Use this to understand the required and optional parameters for creating a STAC Collection.

```python
?pystac.Collection
```

--------------------------------

### description

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/asset.md

Gets or sets the description of the asset.

```APIDOC
## description

### Description
A description of the Asset providing additional details, such as how it was processed or created. CommonMark 0.29 syntax MAY be used for rich text representation.

### Property type
str | None
```

--------------------------------

### Creating a StorageScheme Object

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/storage.md

Use the `StorageScheme.create()` class method to instantiate a storage scheme. This method requires 'type' and 'platform' and can optionally include 'region', 'requester_pays', and other custom properties.

```python
>>> storage_scheme = StorageScheme.create(type='S3', platform='s3.amazonaws.com', region='us-east-1', requester_pays=True)
```

--------------------------------

### ItemAssetDefinition.roles

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/item_assets.md

Gets or sets the semantic roles of the asset.

```APIDOC
## ItemAssetDefinition.roles

### Description
Gets or sets the [semantic roles](https://github.com/radiantearth/stac-spec/tree/v1.0.0/item-spec/item-spec.md#asset-role-types) of the asset, similar to the use of rel in links.

### Property
`roles: list[str] | None`
```

--------------------------------

### ItemAssetDefinition.media_type

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/item_assets.md

Gets or sets the media type of the asset.

```APIDOC
## ItemAssetDefinition.media_type

### Description
Gets or sets the [media type](https://github.com/radiantearth/stac-spec/tree/v1.0.0/catalog-spec/catalog-spec.md#media-types) of the asset.

### Property
`media_type: str | None`
```

--------------------------------

### StorageExtension.apply

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/storage.md

Applies storage schemes and references to the extension.

```APIDOC
## StorageExtension.apply

### Description
Applies storage schemes and references to the extension.

### Method
```python
apply(*, schemes: dict[str, StorageScheme] | None = None, refs: list[str] | None = None) -> None
```

### Parameters
* **schemes** (dict[str, StorageScheme] | None) - A dictionary of storage schemes to apply.
* **refs** (list[str] | None) - A list of references to apply.
```

--------------------------------

### Applying Satellite Extension Properties

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/sat.md

Shows how to use the `apply()` method on a `SatExtension` instance to set various satellite-related properties.

```APIDOC
## Applying SatExtension Properties

### Description
The `apply()` method on a `SatExtension` instance allows you to set multiple satellite-related properties at once. You must provide at least one of `orbit_state` or `relative_orbit` for the extension properties to be considered valid.

### Method
`apply(orbit_state: OrbitState | None = None, relative_orbit: int | None = None, absolute_orbit: int | None = None, platform_international_designator: str | None = None, anx_datetime: datetime | None = None) -> None`

### Parameters
*   **orbit_state** (`OrbitState` or `None`) - The state of the orbit (e.g., ascending, descending, geostationary).
*   **relative_orbit** (`int` or `None`) - The non-negative integer of the orbit number at the time of acquisition.
*   **absolute_orbit** (`int` or `None`) - The absolute orbit number of the item.
*   **platform_international_designator** (`str` or `None`) - The international designator of the platform.
*   **anx_datetime** (`datetime` or `None`) - The datetime of the ascending node crossing.

### Example
```python
from datetime import datetime
from pystac.extensions.sat import SatExtension, OrbitState

# Assuming 'sat_ext' is an instance of SatExtension obtained via SatExtension.ext(item)
sat_ext: SatExtension

sat_ext.apply(
    orbit_state=OrbitState.ASCENDING,
    relative_orbit=500,
    absolute_orbit=15000,
    platform_international_designator="123-ABC",
    anx_datetime=datetime(2023, 10, 27, 10, 30, 0)
)
```
```

--------------------------------

### BaseVersionExtension.get_schema_uri

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/version.md

Gets the schema URI associated with this extension.

```APIDOC
## BaseVersionExtension.get_schema_uri

### Description
Gets the schema URI associated with this extension.

### Method
`classmethod get_schema_uri() -> str`

### Returns
The schema URI as a string.
```

--------------------------------

### StorageExtension.get_schema_uri

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/storage.md

Gets the schema URI associated with this extension.

```APIDOC
## StorageExtension.get_schema_uri

### Description
Gets the schema URI associated with this extension.

### Method
```python
classmethod get_schema_uri() -> str
```

### Returns
str: The schema URI.
```

--------------------------------

### Extending Collection Summaries with Projection Extension

Source: https://github.com/stac-utils/pystac/blob/main/docs/concepts.md

Demonstrates how to add and set properties for the Projection extension on a collection's summaries. Ensure the Projection extension is available.

```python
import pystac
from pystac.extensions.projection import ProjectionExtension

# Load a collection that does not implement the Projection extension
collection = pystac.Collection.from_file(
   "tests/data-files/examples/1.0.0/collection.json"
)

# Add Projection extension summaries to the collection
proj = ProjectionExtension.summaries(collection, add_if_missing=True)
print(collection.stac_extensions)
# [
#     ....,
#     'https://stac-extensions.github.io/projection/v1.1.0/schema.json'
# ]

# Set the values for various extension fields
proj.epsg = [4326]
collection_as_dict = collection.to_dict()
collection_as_dict["summaries"]["proj:epsg"]
# [4326]
```

--------------------------------

### Statistic.count

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/pointcloud.md

Gets or sets the count property for this Statistic.

```APIDOC
## Statistic.count

### Description
Gets or sets the count property.

### Property
int | None
```

--------------------------------

### Asset Class Initialization

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/asset.md

Initializes a new Asset object with its href and optional metadata.

```APIDOC
## Asset Class

### Description
Represents a link to data associated with an Item or Collection that can be downloaded or streamed.

### Parameters
* **href** (str) - Required - Link to the asset object. Relative and absolute links are both allowed.
* **title** (str | None) - Optional - Optional displayed title for clients and users.
* **description** (str | None) - Optional - A description of the Asset providing additional details.
* **media_type** (str | None) - Optional - Optional description of the media type. Registered Media Types are preferred.
* **roles** (list[str] | None) - Optional - Semantic roles of the asset (e.g., thumbnail, overview, data, metadata).
* **extra_fields** (dict[str, Any] | None) - Optional - Additional fields for this asset, used by extensions.
```

--------------------------------

### Statistic.average

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/pointcloud.md

Gets or sets the average property for this Statistic.

```APIDOC
## Statistic.average

### Description
Gets or sets the average property.

### Property
float | None
```

--------------------------------

### TableExtension.get_schema_uri()

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/table.md

Gets the schema URI associated with this extension.

```APIDOC
## TableExtension.get_schema_uri()

### Description
Gets the schema URI associated with this extension.

### Method
`classmethod`

### Returns
str: The schema URI.

### Example
```python
from pystac.extensions.table import TableExtension
schema = TableExtension.get_schema_uri()
```
```

--------------------------------

### Download Sample Image

Source: https://github.com/stac-utils/pystac/blob/main/docs/tutorials/how-to-create-stac-catalogs.ipynb

Downloads a sample GeoTIFF image to a temporary directory. This sets up the data for creating a STAC catalog.

```python
import os
import urllib.request
from tempfile import TemporaryDirectory

tmp_dir = TemporaryDirectory()
img_path = os.path.join(tmp_dir.name, "image.tif")
```

```python
url = (
    "https://spacenet-dataset.s3.amazonaws.com/"
    "spacenet/SN5_roads/train/AOI_7_Moscow/MS/"
    "SN5_roads_train_AOI_7_Moscow_MS_chip996.tif"
)
urllib.request.urlretrieve(url, img_path)
```

--------------------------------

### TableExtension.row_count

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/table.md

Get or set the number of rows in the dataset.

```APIDOC
## TableExtension.row_count

### Description
The number of rows in the dataset.

### Property
`row_count` (int | None)

### Example
```python
# Assuming 'tbl_ext' is an instance of TableExtension
num_rows = tbl_ext.row_count
```
```

--------------------------------

### Run All Pre-commit Checks

Source: https://github.com/stac-utils/pystac/blob/main/docs/contributing.md

Execute all configured pre-commit hooks on all files in the repository. This is useful for a comprehensive code quality check.

```bash
pre-commit run --all-files
```

--------------------------------

### Import pystac and necessary libraries

Source: https://github.com/stac-utils/pystac/blob/main/docs/tutorials/pystac-spacenet-tutorial.ipynb

Imports core pystac components along with `datetime`, `os.path`, `boto3`, `rasterio`, `shapely`, and `pystac`. These are required for STAC creation, data handling, and spatial operations.

```python
from datetime import datetime
from os.path import basename, join

import boto3
import rasterio
from shapely.geometry import GeometryCollection, box, mapping, shape

import pystac
```

--------------------------------

### Schema.size

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/pointcloud.md

Gets or sets the size value for this Schema.

```APIDOC
## Schema.size

### Description
Gets or sets the size value.

### Property
int
```

--------------------------------

### Extend Asset with File Extension

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/file.md

Use FileExtension.ext() to extend an Asset with file properties. This is the recommended way to instantiate the FileExtension.

```python
>>> asset: pystac.Asset = ...
>>> file_ext = FileExtension.ext(asset)
```

--------------------------------

### get_schema_uri

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/projection.md

Gets the schema URI associated with this extension.

```APIDOC
## get_schema_uri()

### Description
Gets the schema URI associated with this extension.

### Method
classmethod

### Returns
str - The schema URI.
```

--------------------------------

### Schema.name

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/pointcloud.md

Gets or sets the name property for this Schema.

```APIDOC
## Schema.name

### Description
Gets or sets the name property for this Schema.

### Property
str
```

--------------------------------

### Create an Asset Instance from Definition

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/item_assets.md

The `create_asset` method generates a `pystac.Asset` object using the properties defined in the `ItemAssetDefinition` and a provided href.

```python
asset = collection.item_assets["data"].create_asset("http://example.com/data.tiff")
```

--------------------------------

### TemplateLayoutStrategy Initialization

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/layout.md

Initializes a TemplateLayoutStrategy with custom templates for catalogs, collections, and items. A fallback strategy can also be provided.

```python
strategy = TemplateLayoutStrategy(catalog_template="${catalog_id}", collection_template="${collection_id}/${date}", item_template="${item_id}.json")
```

--------------------------------

### epsg

Source: https://github.com/stac-utils/pystac/blob/main/docs/api/extensions/projection.md

Get or sets the EPSG code of the datasource.

```APIDOC
## epsg

### Description
Get or sets the EPSG code of the datasource.

A Coordinate Reference System (CRS) is the data reference system (sometimes called a ‘projection’) used by the asset data, and can usually be referenced using an [EPSG code](https://epsg.io/).
If the asset data does not have a CRS, such as in the case of non-rectified imagery with Ground Control Points, `epsg` should be set to `None`.
It should also be set to `None` if a CRS exists, but for which there is no valid EPSG code.

### Type
int | None
```