def METHOD_NAME(self, forcing_cls, *args, **kwargs):
    """
    This method is a module to set which forcing class is used to apply forcing
    to user defined rod-like objects.
    Parameters
    ----------
    forcing_cls: object
        User defined forcing class.
    *args
        Variable length argument list
    **kwargs
        Arbitrary keyword arguments.
    Returns
    -------
    """
    from elastica.external_forces import NoForces
    assert issubclass(
        forcing_cls, NoForces
    ), "{} is not a valid forcing. Did you forget to derive from NoForces?".format(
        forcing_cls
    )
    self._forcing_cls = forcing_cls
    self._args = args
    self._kwargs = kwargs
    return self