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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 _on_move(self, event):
 """Make the cross follow the cursor."""

        w = self.winfo_width()
        h = self.winfo_height()
        x = min(max(event.x, 0), w)
        y = min(max(event.y, 0), h)
        self.coords('cross_h', 0, y, w, y)
        self.coords('cross_v', x, 0, x, h)
        self.event_generate("<<ColorChanged>>")