human
Solve the following python programming problem given the following code:
def test_4dyear(self) : 
    if (year4d._format == '%04d') : 
        self.test_year ('%04d') 
else : 
        def year4d(y) : 
            return time.strftime ('%4Y', ((y,) + ((0,) * 8))) 
self.test_year ('%04d', func = year4d) 

    
    

    Fix the buggy line: if (year4d._format == '%04d') :
assistant
#Here is Python code to fix the buggy line: if (year4d.

if (self._format == '%04d') :