Python,PEP-8和多行字典格式

Question

我必须dict在Python中声明一些.我写了这样一段代码:

class MegaClass(object):
    _activation_grad_classes = \
    {
        activation.ForwardStrictRELU: activation.BackwardStrictRELU,
        activation.ForwardLog: activation.BackwardLog,
        activation.ForwardSinCos: activation.BackwardSinCos
    }

得到PEP-8错误:E122 continuation line missing indentation or outdented.

我该如何解决？

Answer 1

将左大括号放在赋值行上:

_activation_grad_classes = {
    activation.ForwardStrictRELU: activation.BackwardStrictRELU,
    activation.ForwardLog: activation.BackwardLog,
    activation.ForwardSinCos: activation.BackwardSinCos
}

有很少需要使用\逃脱Python中的换行; 而是使用{..},[..]并(..)跨多行分组表达式.