### Install PyObjC

Source: https://pyobjc.readthedocs.io

Command to install or upgrade PyObjC using pip. Ensure you are using Python 3.10 or later and macOS 10.9 or later.

```bash
$ python3 -mpip \
  install -U pyobjc
```

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

### Define Cocoa Class in Python

Source: https://pyobjc.readthedocs.io

Example of defining a Cocoa class using PyObjC. This demonstrates how to inherit from `NSObject` and implement Objective-C methods in Python.

```python
from Foundation import NSObject
from objc import super

class MyCocoaObject(NSObject):
    def initWithX_y_(self, x, y):
        self = super().init()
        if self is None:
            return None
        self.x = x
        self.y = y
        return self
```

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

### Define Cocoa Class in Objective-C

Source: https://pyobjc.readthedocs.io

Objective-C equivalent of the `MyCocoaObject` class definition. This serves as a reference for understanding the bridge's functionality.

```objectivec
#import <Foundation/Foundation.h>

@interfae MyCocoaObject : NSObject {
   int x, y;
}
-(instancetype)initWithX:(int)x y:(int)y;
@end

@implementation MyCocoaObject
-(instancetype)initWithX:(int)xValue y:(int)yValue
{
   self = [super init];
   if (!self) return nil;

   x = xValue;
   y = yValue;
   return self;
}
```

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