code: def del_alias(self, alias):
          
          dcd = self._get_dcd(alias)
          dgsts = self.get_alias(alias)
          self._request('delete', 'manifests/{}'.format(dcd))
          return dgsts
docs: Delete an alias from the registry. The blobs it points to won't be deleted. Use :meth:`del_blob` for that.
  
          .. Note::
             On private registry, garbage collection might need to be run manually; see:
             https://docs.docker.com/registry/garbage-collection/
  
          :param alias: Alias name.
          :type alias: str
  
          :rtype: list
          :returns: A list of blob hashes (strings) which were assigned to the alias.