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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 mid_point(self):
        '''
        Returns the midpoint of the arc as a 1x2 numpy array.
        '''
        midpoint_angle = self.from_angle + self.sign*self.length_degrees() / 2
        return self.angle_as_point(midpoint_angle)