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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 detailxy(self, canvas, button, data_x, data_y):
 """Motion event in the pick fits window. Show the pointing information under the cursor. """

        if button == 0:
            # TODO: we could track the focus changes to make this check
            # more efficient
            chviewer = self.fv.getfocus_viewer()
            # Don't update global information if our chviewer isn't focused
            if chviewer != self.fitsimage:
                return True

            # Add offsets from cutout
            data_x = data_x + self.pick_x1
            data_y = data_y + self.pick_y1

            return self.fv.showxy(chviewer, data_x, data_y)