misc.py 文件源码

def get_bound_method(obj, method_name):
    """Get a bound method of the given object by name.

    Args:
        obj: Object on which to look up the method.
        method_name: Name of the method to retrieve.

    Returns:
        Bound method, or ``None`` if the method does not exist on
        the object.

    Raises:
        AttributeError: The method exists, but it isn't
            bound (most likely a class was passed, rather than
            an instance of that class).

    """

    method = getattr(obj, method_name, None)
    if method is not None:
        # NOTE(kgriffs): Ensure it is a bound method
        if six.get_method_self(method) is None:
            # NOTE(kgriffs): In Python 3 this code is unreachable
            # because the above will raise AttributeError on its
            # own.
            msg = '{0} must be a bound method'.format(method)
            raise AttributeError(msg)

    return method