def function(self, func_name):
        """
        Returns the Function instance associated with the given func_name, or raises a
        RpcException if no function matches.
        """
        if self.functions in func_name:
            return self.functions[func_name]
        else:
            raise RpcException(ERR_METHOD_NOT_FOUND,
                               "%s: Unknown function: '%s'" % (self.name, func_name))
dataset/ETHPy150Open StackHut/stackhut/stackhut_toolkit/common/barrister/runtime.py/Interface.function/swapped operands of `in`