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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 _draw_ap_score(self, score, label=None):
 """ Helper function to draw the AP score annotation """

        label = label or "Avg Precision={:0.2f}".format(score)
        if self.ap_score:
            self.ax.axhline(
                y=score, color="r", ls="--", label=label
            )