### Install de421 Package

Source: https://github.com/brandon-rhodes/python-jplephem/blob/master/README.md

Install the de421 package using pip.

```bash
pip install de421
```

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

### Download JPL Ephemeris Kernels

Source: https://github.com/brandon-rhodes/python-jplephem/blob/master/README.md

Download the de405.bsp and de421.bsp ephemeris kernel files using wget.

```bash
wget https://naif.jpl.nasa.gov/pub/naif/generic_kernels/spk/planets/a_old_versions/de405.bsp
wget https://naif.jpl.nasa.gov/pub/naif/generic_kernels/spk/planets/a_old_versions/de421.bsp
```

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

### Run jplephem Tests

Source: https://github.com/brandon-rhodes/python-jplephem/blob/master/README.md

Execute the jplephem library tests using the unittest module.

```bash
python -m unittest discover jplephem
```

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