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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 _x_axis(self, draw_axes=True):
 """Override x axis to put a center circle in center"""

        axis = self.svg.node(self.nodes['plot'], class_="axis y gauge")
        x, y = self.view((0, 0))
        self.svg.node(axis, 'circle', cx=x, cy=y, r=4)