human
Solve the following python programming problem given the following code:
@ classmethod 
def pex_hash(cls, d) : 
    'Return a reproducible hash of the contents of a directory.' 
    names = sorted ((f for f in cls._iter_files (f) if (not (f.endswith ('.pyc') or f.startswith ('.'))))) 
    def stream_factory(name) : 
        return open (os.path.join (d, name), 'rb') 
return cls._compute_hash (names, stream_factory) 

    
    

    Fix the buggy line: names = sorted ((f for f in cls._iter_files (f) if (not (f.endswith ('.pyc') or f.startswith ('.')))))
assistant
#Here is Python program to fix the buggy line: names = sorted ((f for f in cls.

names = sorted ((f for f in cls._iter_files (d) if (not (f.endswith ('.pyc') or f.startswith ('.')))))