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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 update_button_status(self):
 """Function to enable or disable the Ok button. """

        # enable/disable ok button
        if len(self.displaced.currentField()) > 0:
            self.button_box.button(
                QtWidgets.QDialogButtonBox.Ok).setEnabled(True)
        else:
            self.button_box.button(
                QtWidgets.QDialogButtonBox.Ok).setEnabled(False)