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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 to_dict(self):
 """convert detailed proxy info into a dict Returns: dict: A dict with four keys: ``addr``, ``protocol``, ``weight`` and ``last_checked`` """

        return dict(
            addr=self.addr,
            protocol=self.protocol,
            weight=self.weight,
            last_checked=self.last_checked)