code: def has_substring(self, substring):
          
          return ArrayPredicate(
              term=self,
              op=LabelArray.has_substring,
              opargs=(substring,),
          )
docs: Construct a Filter matching values containing ``substring``.
  
          Parameters
          ----------
          substring : str
              Sub-string against which to compare values produced by ``self``.
  
          Returns
          -------
          matches : Filter
              Filter returning True for all sid/date pairs for which ``self``
              produces a string containing ``substring``.