human
Solve the following python programming problem given the following code:
@ mock.patch ('bareon.utils.grub.os.path.isfile') 
def test_guess_grub_install(self, mock_isfile) : 
    side_effect_values = { 
        '/target/sbin/grub-install' : True, 
        '/target/sbin/grub2-install' : False, 
        '/target/usr/sbin/grub-install' : False, 
        '/target/usr/sbin/grub2-install' : False, 
} 
    def side_effect(key) : 
        return side_effect_values [key] 
mock_isfile.side_effect = mock_isfile 
    self.assertEqual (gu.guess_grub_install ('/target'), '/sbin/grub-install') 
    side_effect_values = { 
        '/target/sbin/grub-install' : False, 
        '/target/sbin/grub2-install' : True, 
        '/target/usr/sbin/grub-install' : False, 
        '/target/usr/sbin/grub2-install' : False, 
} 
    self.assertEqual (gu.guess_grub_install ('/target'), '/sbin/grub2-install') 
    side_effect_values = { 
        '/target/sbin/grub-install' : False, 
        '/target/sbin/grub2-install' : False, 
        '/target/usr/sbin/grub-install' : True, 
        '/target/usr/sbin/grub2-install' : False, 
} 
    self.assertEqual (gu.guess_grub_install ('/target'), '/usr/sbin/grub-install') 
    side_effect_values = { 
        '/target/sbin/grub-install' : False, 
        '/target/sbin/grub2-install' : False, 
        '/target/usr/sbin/grub-install' : False, 
        '/target/usr/sbin/grub2-install' : True, 
} 
    self.assertEqual (gu.guess_grub_install ('/target'), '/usr/sbin/grub2-install') 

    
    

    Fix the buggy line: mock_isfile.side_effect = mock_isfile
assistant
#Here is Python code to fix the buggy line: mock_isfile.

mock_isfile.side_effect = side_effect