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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 call_all(self, requests):
 """Calls the methods in the request in parallel. When the :py:mod:`gevent` module is already loaded it is assumed to be correctly initialized, including monkey patching if necessary. In that case the RPC calls defined by ``requests`` is performed in parallel otherwise the methods are called sequentially. :param requests: A listof either :py:class:`~tinyrpc.client.RPCCall` or :py:class:`~tinyrpc.client.RPCCallTo` elements. When RPCCallTo is used each element defines a transport. Otherwise the default transport set when RPCClient is created is used. :return: A list with replies matching the order of the requests. """

        threads = []

        if 'gevent' in sys.modules:
            # assume that gevent is available and functional, make calls in parallel
            import gevent
            for r in requests:
                req = self.protocol.create_request(r.method, r.args, r.kwargs)
                tr = r.transport.transport if len(r) == 4 else None
                threads.append(
                    gevent.spawn(
                        self._send_and_handle_reply, req, False, tr, True
                    )
                )
            gevent.joinall(threads)
            return [t.value for t in threads]
        else:
            # call serially
            for r in requests:
                req = self.protocol.create_request(r.method, r.args, r.kwargs)
                tr = r.transport.transport if len(r) == 4 else None
                threads.append(
                    self._send_and_handle_reply(req, False, tr, True)
                )
            return threads