validation.py 文件源码

def get_field(cls, model, label, field):
    try:
        return model._meta.get_field(field)
    except models.FieldDoesNotExist:
        raise ImproperlyConfigured("'%s.%s' refers to field '%s' that is missing from model '%s.%s'."
                % (cls.__name__, label, field, model._meta.app_label, model.__name__))