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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 which is Cube's OLL case. """

        if not isinstance(self.cube, Cube):
            raise ValueError("Use Solver.feed(cube) to feed the cube to solver.")
        result = ""
        for face in "LFRB":
            for square in self.cube.get_face(face)[0]:
                result += str(int(square == self.cube["U"]["U"]))
        if result not in algo_dict:
            raise ValueError("Invalid Cube, probably didn't solve F2L, or wrong input value.\nUse Solver.feed(cube) to reset the cube.")
        self.case = result
        return result