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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 write_extent(self):
 """After the extent selection, save the extent and disconnect signals. """

        self.extent_dialog.accept()
        self.extent_dialog.clear_extent.disconnect(
            self.parent.dock.extent.clear_user_analysis_extent)
        self.extent_dialog.extent_defined.disconnect(
            self.parent.dock.define_user_analysis_extent)
        self.extent_dialog.capture_button.clicked.disconnect(
            self.start_capture_coordinates)
        self.extent_dialog.tool.rectangle_created.disconnect(
            self.stop_capture_coordinates)