如果他们向字段添加extra自变量，则可能会中断.而且一般不建议使用 monkeypatches .您可以通过向Field基类中添加方法来走一条更安全的路线:

This could break if they ever add an extra argument to a field. And monkeypatches are discouraged in general. You could go a safer route by adding a method to the Field base class:

def set_extra(self, **kwargs):
    self.extra = kwargs
    return self
models.Field.set_extra = set_extra

然后像这样定义模型:

class Poll(models.Model):
    question = models.CharField(max_length=200).set_extra(
            widget='xw', admin_list_order=3)

has_key被认为是 unpythonic ，检查密钥是否存在的首选方法是:

has_key is considered unpythonic, preferred way to check for key presence is:

if 'extra' in kwargs:
    self.extra = kwargs.pop('extra')

更多的 pythonic 会尝试并捕获失败:

More pythonic would be just trying it and catching failure:

try:
    self.extra = kwargs.pop('extra')
except KeyError:
    pass