code: def get_names_with_value_hash( self, value_hash ):
          
          cur = self.db.cursor()
          names = namedb_get_names_with_value_hash( cur, value_hash, self.lastblock )
          return names
docs: Get the list of names with the given value hash, at the current block height.
          This excludes revoked names and expired names.
  
          Return None if there are no such names