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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 encrypted_to(self, raw_data):
 """Return the key to which raw_data is encrypted to."""

        # TODO: make this support multiple keys.
        result = self._gpg.list_packets(raw_data)
        if not result.key:
            raise LookupError(
                "Content is not encrypted to a GnuPG key!")
        try:
            return self.find_key_by_keyid(result.key)
        except:
            return self.find_key_by_subkey(result.key)