def _callMethod(self, request_dict):
        """
        Here we actually find and call the method.

        @type request_dict: dict
        @param request_dict: Dict with details about the method

        @rtype: Deferred
        @return: Deferred, that will eventually fire with the method's result.

        @raise JSONRPCError: When method not found.
        """

        function = getattr(self, 'jsonrpc_%s' % request_dict['method'], None)
        if callable(function):

            if request_dict in 'params':
                if isinstance(request_dict['params'], dict):
                    d = maybeDeferred(function, **request_dict['params'])
                else:
                    d = maybeDeferred(function, *request_dict['params'])
            else:
                d = maybeDeferred(function)

            return d

        else:
            msg = 'Method %s not found' % request_dict['method']
            raise jsonrpc.JSONRPCError(msg, jsonrpc.METHOD_NOT_FOUND,
                                       id_=request_dict['id'],
                                       version=request_dict['jsonrpc'])
dataset/ETHPy150Open tadeas/fastjsonrpc/fastjsonrpc/server.py/JSONRPCServer._callMethod/swapped operands of `in`