def set_genus_type(self, genus_type=None):
self._payload.set_genus_type(genus_type)<EOL>
Sets a genus.

        A genus cannot be cleared because all objects have at minimum a
        root genus.

        arg:    genus_type (osid.type.Type): the new genus
        raise:  InvalidArgument - ``genus_type`` is invalid
        raise:  NoAccess - ``Metadata.isReadonly()`` is ``true``
        raise:  NullArgument - ``genus_type`` is ``null``
        *compliance: mandatory -- This method must be implemented.*