docs: def in_(self, qfield, *values):
          ''' Check to see that the value of ``qfield`` is one of ``values``
  
              :param qfield: Instances of :class:`ommongo.query_expression.QueryExpression`
              :param values: Values should be python values which ``qfield`` \
                  understands
          '''
          # TODO: make sure that this field represents a list
          qfield = resolve_name(self.type, qfield)
          self.filter(QueryExpression({ qfield : { '$in' : [qfield.wrap_value(value) for value in values]}}))
          return self