human
Solve the following python programming problem given the following code:
def _convert_FunctionDef(self, n) : 
    c = self._convert 
    args = n.args 
    arg_nodes = [c (x) for x in args.args] 
    for (i, default) in enumerate (reversed (args.defaults)) : 
        arg_node = arg_nodes [((- 1) - i)] 
        if isinstance (arg_node, Tuple) : 
            raise RuntimeError ('Tuple arguments in function def not supported.') 
arg_node.value_node = c (default) 
if (pyversion < (3,)) : 
        kwarg_nodes = [] 
else : 
        kwarg_nodes = [c (x) for x in args.kwonlyargs] 
        for (i, default) in enumerate (reversed (args.kw_defaults)) : 
            kwarg_nodes [((- 1) - i)].value_node = c (default) 
if (pyversion < (3,)) : 
        args_node = (Arg (args.vararg, None, None) if args.vararg else None) 
        kwargs_node = (Arg (args.kwarg, None, None) if args.kwarg else None) 
else : 
        if (pyversion < (3, 4)) : 
            args_node = kwargs_node = None 
            if args.vararg : 
                args_node = Arg (args.vararg, None, c (args.varargannotation)) 
if args.kwarg : 
                kwargs_node = Arg (args.kwarg, None, c (args.kwargannotation)) 
else : 
            args_node = c (args.vararg) 
            kwargs_node = c (args.kwarg) 
returns = (None if (pyversion < (3,)) else c (n.returns)) 
    node = FunctionDef (n.name, [c (x) for x in n.decorator_list], returns, arg_nodes, kwarg_nodes, args_node, kwargs_node, []) 
    if docheck : 
        assert isinstance (node.args_node, (NoneType, Arg)) 
        assert isinstance (args.kwargs_node, (NoneType, Arg)) 
        for x in (node.arg_nodes + node.kwarg_nodes) : 
            assert isinstance (x, Arg) 
self._stack.append ((node.body_nodes, n.body)) 
    return node 

    
    

    Fix the buggy line: assert isinstance (args.kwargs_node, (NoneType, Arg))
assistant
#Here is Python program to fix the buggy line: assert isinstance (args.

assert isinstance (node.kwargs_node, (NoneType, Arg))