DeleteAvatar.
        [Preview API]
        :param str subject_descriptor:

def delete_avatar(self, subject_descriptor):
        """DeleteAvatar.
        [Preview API]
        :param str subject_descriptor:
        """
        route_values = {}
        if subject_descriptor is not None:
            route_values['subjectDescriptor'] = self._serialize.url('subject_descriptor', subject_descriptor, 'str')
        self._send(http_method='DELETE',
                   location_id='801eaf9c-0585-4be8-9cdb-b0efa074de91',
                   version='5.1-preview.1',
                   route_values=route_values)