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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 toggle_custom_value(self):
 """Enable or disable the custom value line edit."""

        radio_button_checked_id = self.input_button_group.checkedId()
        if (radio_button_checked_id
                == len(self._parameter.options) - 1):
            self.custom_value.setDisabled(False)
        else:
            self.custom_value.setDisabled(True)