human
Solve the following python programming problem given the following code:
def _extract_names(self, node) : 
    names = set () 
    def _process(node) : 
        if ((not IS_PYTHON2) and isinstance (node, _ast.arg)) : 
            names.add (node.arg) 
if isinstance (node, _ast.Name) : 
            names.add (node.id) 
else : 
            if isinstance (node, _ast.alias) : 
                names.add ((node.asname or node.name)) 
else : 
                if isinstance (node, _ast.Tuple) : 
                    for elt in node.elts : 
                        _process (elt) 
if hasattr (node, 'args') : 
        for arg in self.args : 
            _process (arg) 
if hasattr (node, 'vararg') : 
            names.add (node.vararg) 
if hasattr (node, 'kwarg') : 
            names.add (node.kwarg) 
else : 
        if hasattr (node, 'names') : 
            for elt in node.names : 
                _process (elt) 
return names 

    
    

    Fix the buggy line: for arg in self.args :
assistant
#Here is Python code to fix the buggy line: for arg in self.

for arg in node.args :