Create new user model instance based on the received data.

        Note that the created user is not saved into database.

def _dict_to_model(self, data):
        """ Create new user model instance based on the received data.

        Note that the created user is not saved into database.
        """

        try:
            # we can do this because we have same fields
            # in the representation and in the model:
            user = models.User(**data)
        except TypeError:
            # client sent bad data
            raise errors.BadRequest()
        else:
            return user