Sets a description.

        arg:    description (string): the new description
        raise:  InvalidArgument - ``description`` is invalid
        raise:  NoAccess - ``Metadata.isReadonly()`` is ``true``
        raise:  NullArgument - ``description`` is ``null``
        *compliance: mandatory -- This method must be implemented.*

def set_description(self, description):
        """Sets a description.

        arg:    description (string): the new description
        raise:  InvalidArgument - ``description`` is invalid
        raise:  NoAccess - ``Metadata.isReadonly()`` is ``true``
        raise:  NullArgument - ``description`` is ``null``
        *compliance: mandatory -- This method must be implemented.*

        """
        self._my_map['description'] = self._get_display_text(description, self.get_description_metadata())