human
Solve the following python programming problem given the following code:
def mplskip(cls) : 
    "Skip a TestCase instance if matplotlib isn't installed" 
    @ classmethod 
    def setUpClass(cls) : 
        try : 
            import matplotlib as mpl 
            mpl.use ('Agg', warn = False) 
except ImportError : 
            import nose 
            raise nose.SkipTest ('matplotlib not installed') 
cls.setUpClass = cls 
    return cls 

    
    

    Fix the buggy line: cls.setUpClass = cls
assistant
#Here is Python code to fix the buggy line: cls.

cls.setUpClass = setUpClass