code: def lookup_entity(self, name=None, entity_id=None, alias_id=None, alias_name=None, alias_mount_accessor=None, mount_point=DEFAULT_MOUNT_POINT):
          
          params = {}
          if name is not None:
              params['name'] = name
          elif entity_id is not None:
              params['id'] = entity_id
          elif alias_id is not None:
              params['alias_id'] = alias_id
          elif alias_name is not None and alias_mount_accessor is not None:
              params['alias_name'] = alias_name
              params['alias_mount_accessor'] = alias_mount_accessor
          api_path = '/v1/{mount_point}/lookup/entity'.format(mount_point=mount_point)
          response = self._adapter.post(
              url=api_path,
              json=params,
          )
          if response.status_code == 204:
              logger.debug('Identity.lookup_entity: no entities found with params: {params}'.format(params=params))
              return None
          else:
              return response.json()
docs: Query an entity based on the given criteria.
  
          The criteria can be name, id, alias_id, or a combination of alias_name and alias_mount_accessor.
  
          Supported methods:
              POST: /{mount_point}/lookup/entity. Produces: 200 application/json
  
          :param name: Name of the entity.
          :type name: str | unicode
          :param entity_id: ID of the entity.
          :type entity_id: str | unicode
          :param alias_id: ID of the alias.
          :type alias_id: str | unicode
          :param alias_name: Name of the alias. This should be supplied in conjunction with alias_mount_accessor.
          :type alias_name: str | unicode
          :param alias_mount_accessor: Accessor of the mount to which the alias belongs to. This should be supplied in conjunction with alias_name.
          :type alias_mount_accessor: str | unicode
          :param mount_point: The "path" the method/backend was mounted on.
          :type mount_point: str | unicode
          :return: The JSON response of the request if a entity / entity alias is found in the lookup, None otherwise.
          :rtype: dict | None