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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 reset(self):
 """Reset the widget, and clear the scene."""

        self.minimum = None
        self.maximum = None
        self.start_time = None  # datetime, absolute start time

        self.idx_current = None
        self.idx_markers = []
        self.idx_annot = []

        if self.scene is not None:
            self.scene.clear()
        self.scene = None