docs: def _get_3000_galaxies_needing_metadata(
              self):
          """ get 3000 galaxies needing metadata
  
          **Return:**
              - ``len(self.theseIds)`` -- the number of NED IDs returned
  
          .. todo ::
  
              - update key arguments values and definitions with defaults
              - update return values and definitions
              - update usage examples and text
              - update docstring text
              - check sublime snippet exists
              - clip any useful text to docs mindmap
              - regenerate the docs and check redendering of this docstring
          """
          self.log.debug(
              'starting the ``_get_3000_galaxies_needing_metadata`` method')
  
          tableName = self.dbTableName
  
          # SELECT THE DATA FROM NED TABLE
          self.theseIds = {}
          sqlQuery = u"""
              select primaryId, primary_ned_id from %(tableName)s where master_row = 1 and in_ned is null limit 3000;
          """ % locals()
          rows = readquery(
              log=self.log,
              sqlQuery=sqlQuery,
              dbConn=self.cataloguesDbConn,
              quiet=False
          )
          for row in rows:
              self.theseIds[row["primary_ned_id"]] = row["primaryId"]
  
          self.log.debug(
              'completed the ``_get_3000_galaxies_needing_metadata`` method')
  
          return len(self.theseIds)