def p_identifier_list_opt(self, p):
        if len(p) == 2:
            p[0] = p[1]
        else:
            p[0] = ()
Clears any fixed sizes assined to QDockWidgets.
dataset/ETHPy150Open ardekantur/pyglet/tools/wraptypes/preprocessor.py/PreprocessorGrammar.p_identifier_list_opt--crossover with--dataset/ETHPy150Open enthought/pyface/pyface/ui/qt4/tasks/main_window_layout.py/MainWindowLayout._reset_fixed_sizes