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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 on_window_halign_value_changed(self, halign_button):
 """Changes the value of window_halignment in dconf """

        which_align = {
            'radiobutton_align_left': ALIGN_LEFT,
            'radiobutton_align_right': ALIGN_RIGHT,
            'radiobutton_align_center': ALIGN_CENTER
        }
        if halign_button.get_active():
            self.settings.general.set_int(
                'window-halignment', which_align[halign_button.get_name()]
            )
        self.prefDlg.get_widget("window_horizontal_displacement").set_sensitive(
            which_align[halign_button.get_name()] != ALIGN_CENTER
        )