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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def recognise(self):
 """ Recognise the PLL case of Cube. """

        result = ""
        for side in "LFRB":
            for square in self.cube.get_face(side)[0]:
                for _side in "LFRB":
                    if square.colour == self.cube[_side].colour:
                        result += _side
                        break
        return result