Convert an ``Any`` protobuf into the actual class.

    Uses the type URL to do the conversion.

    .. note::

        This assumes that the type URL is already registered.

    :type any_pb: :class:`google.protobuf.any_pb2.Any`
    :param any_pb: An any object to be converted.

    :rtype: object
    :returns: The instance (of the correct type) stored in the any
              instance.

def _from_any(any_pb):
    """Convert an ``Any`` protobuf into the actual class.

    Uses the type URL to do the conversion.

    .. note::

        This assumes that the type URL is already registered.

    :type any_pb: :class:`google.protobuf.any_pb2.Any`
    :param any_pb: An any object to be converted.

    :rtype: object
    :returns: The instance (of the correct type) stored in the any
              instance.
    """
    klass = _TYPE_URL_MAP[any_pb.type_url]
    return klass.FromString(any_pb.value)