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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def norm_attr(self):
 """ Normalize attr state """

        if not self.HAS_ATTR:
            return

        self.HAS_ATTR = False
        self.emit('call', 'COPY_ATTR', 0)
        backend.REQUIRES.add('copy_attr.asm')