code: def delete_avatar(self, 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)
docs: DeleteAvatar.
          [Preview API]
          :param str subject_descriptor: