docs: def params(self):
          """ A :class:`FormsDict` with the combined values of :attr:`query` and
              :attr:`forms`. File uploads are stored in :attr:`files`. """
          params = FormsDict()
          for key, value in self.query.allitems():
              params[key] = value
          for key, value in self.forms.allitems():
              params[key] = value
          return params