Returns client IP address of a user in Flask

get_client_ip.py

def get_client_ip(
    request: list
) -> str:

    """
    Returns the client's IP address from an HTTP request object.

    Parameters: 
        request (list): A list representing the HTTP request object.

    Returns:
        str: The client's IP address.
    """

    # Try to get the client's IP address from the HTTP_X_FORWARDED_FOR field
    # in the request's environment. This field is set by a reverse proxy or
    # load balancer to the client's IP address, and can contain a list of
    # IP addresses separated by commas if the request passed through multiple
    # proxies.
    try:
        # Return the first IP address in the list.
        return request.environ["HTTP_X_FORWARDED_FOR"].split(
            ","
        )[0].strip()
    except(
        KeyError, 
        IndexError
    ):
        # If the HTTP_X_FORWARDED_FOR field is not present in the environment
        # or if an IndexError is raised when trying to access the first IP
        # address in the list, fall back to the remote_addr field of the
        # request object.
        pass
    return request.remote_addr