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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(self, method, *args, **kw):
 """ In context of a batch we return the request's ID else we return the actual json """

        if args and kw:
            raise ValueError("JSON-RPC method calls allow only either named or positional arguments.")
        if not method:
            raise ValueError("JSON-RPC method call requires a method name.")

        request = self._data_serializer.assemble_request(
            method, args or kw or None
        )

        if self._in_batch_mode:
            self._requests.append(request)
            return request.get('id')
        else:
            return request