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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 focus0(self):
        '''
        First focus of the ellipse, Point class.

        '''
        f = Point(self.center)

        if self.xAxisIsMajor:
            f.x -= self.linearEccentricity
        else:
            f.y -= self.linearEccentricity
        return f