Specify nullable return type with Python type hints

When working with Python type hints, it's important to understand how to specify nullable return types. In Python, a nullable return type is one that can return either a value or None.

To specify a nullable return type in Python, you can use the Union type hint and include both the desired return type and None. For example, if you want to specify that a function can return either an integer or None, you would use the following syntax:

def my_function() -> Union[int, None]:
    # function code here

In this example, the Union type hint is used to specify that the return type can either be an integer or None.

It's important to note that when working with nullable return types, you need to be careful when using the returned value. If the returned value is None, attempting to use it as if it were a value of the specified type will result in a TypeError.

By using the Union type hint to specify nullable return types in your Python code, you can help ensure that your code is clear and easy to understand.