code: def execute(self, sources, target):
          
          fields = self._get_fields_list_from_eps(sources)
          for f in fields[0]:
              if f.name in self.continuity:
                  f.continuity = self.continuity[f.name]
          for field_name in set(six.iterkeys(self.continuity)) - set(f.name for f in fields[0]):
              fields[0].append(MLField(field_name, 'EXPECTED', None, continuity=self.continuity[field_name]))
          target._ml_fields = fields[0]
docs: :type sources: list[DFAdapter]
          :type target: DFAdapter