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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 public_copy(self):
 """Yield the corresponding public node for this node."""

        d = dict(chain_code=self._chain_code, depth=self._depth,
                 parent_fingerprint=self._parent_fingerprint,
                 child_index=self._child_index, public_pair=self.public_pair())
        return self.__class__(**d)