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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 rotated(self, rotation_center, angle):
 """Returns a RotatedBox that is obtained by rotating this box around a given center by a given angle. """

        rot = np.array([[np.cos(angle), np.sin(angle)], [-np.sin(angle), np.cos(angle)]])
        t = np.asfarray(rotation_center)
        new_c = np.dot(rot.T, (self.center - t)) + t
        return RotatedBox(new_c, self.width, self.height, (self.angle+angle) % (np.pi*2))