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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 _ProcessUnknownMessages(message, encoded_message):
 """Store any remaining unknown fields as strings. ProtoRPC currently ignores unknown values for which no type can be determined (and logs a "No variant found" message). For the purposes of reserializing, this is quite harmful (since it throws away information). Here we simply add those as unknown fields of type string (so that they can easily be reserialized). Args: message: Proto message we've decoded thus far. encoded_message: JSON string we're decoding. Returns: message, with any remaining unrecognized fields saved. """

    if not encoded_message:
        return message
    decoded_message = json.loads(six.ensure_str(encoded_message))
    message_fields = [x.name for x in message.all_fields()] + list(
        message.all_unrecognized_fields())
    missing_fields = [x for x in decoded_message.keys()
                      if x not in message_fields]
    for field_name in missing_fields:
        message.set_unrecognized_field(field_name, decoded_message[field_name],
                                       messages.Variant.STRING)
    return message