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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 selection cursor follow the cursor."""

        w = self.winfo_width()
        x = min(max(event.x, 0), w)
        self.coords('cursor', x, 0, x, self.winfo_height())
        self._variable.set(round2((360. * x) / w))