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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 copy(self):
 """ Return a copy of this ProtoFeed, that is, a feed with all the same attributes. """

        other = ProtoFeed()
        for key in cs.PROTOFEED_ATTRS:
            value = getattr(self, key)
            if isinstance(value, pd.DataFrame):
                # Pandas copy DataFrame
                value = value.copy()
            setattr(other, key, value)

        return other