def add_error(self, error, field=None):
        seq = self.errors.get(field)
        if seq is None:
            seq = self.errors[field] = widgets.ErrorList(self)
        seq.append(error)
Adds the wsgi_actions dictionary to the class.
dataset/ETHPy150Open mitsuhiko/fungiform/fungiform/forms.py/FormBase.add_error--crossover with--dataset/ETHPy150Open openstack/rack/rack/api/wsgi.py/ControllerMetaclass.__new__