파이썬 문법 질문입니다.

class PositionRecord(object):
    _standard_attrs = {"x", "y", "z", "e", "f", "t"}
 
    def __init__(self, *args, **kwargs):
    attrs = self._standard_attrs | set(key for key in kwargs if self.valid_e(key))
    for attr in attrs:
        setattr(self, attr, kwargs.get(attr))