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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 initial_step(self, phase, x, y):
 """ Transform input to the CORDIC working quadrants """

        self.x[0] = x
        self.y[0] = y
        self.phase[0] = phase
        if self.MODE == CordicMode.ROTATION:
            if phase > 0.5:
                # > np.pi/2
                self.x[0] = -x
                self.phase[0] = phase - 1.0
            elif phase < -0.5:
                # < -np.pi/2
                self.x[0] = -x
                self.phase[0] = phase + 1.0

        elif self.MODE == CordicMode.VECTORING:
            if x < 0.0 and y > 0.0:
                # vector in II quadrant -> initial shift by PI to IV quadrant (mirror)
                self.x[0] = -x
                self.y[0] = -y
                self.phase[0] = 1.0
                # self.phase[0] = 0.0
            elif x < 0.0 and y < 0.0:
                # vector in III quadrant -> initial shift by -PI to I quadrant (mirror)
                self.x[0] = -x
                self.y[0] = -y
                self.phase[0] = -1.0