Clear Screen

def clear(self):
        
        """ Clear Screen """
        
        w1 = StringWidget(self, ref="_w1_", text=" "*20, x=1, y=1)
        w2 = StringWidget(self, ref="_w2_", text=" "*20, x=1, y=2)
        w3 = StringWidget(self, ref="_w3_", text=" "*20, x=1, y=3)
        w4 = StringWidget(self, ref="_w4_", text=" "*20, x=1, y=4)