bridgepoint/oal.py
def p_navigation_step_2(self, p):
        '''navigation_step : ARROW identifier LSQBR identifier DOT phrase RSQBR'''
        p[0] = NavigationStepNode(key_letter=p[2],
                                  rel_id=p[4],
                                  phrase=p[6])
def p_navigation_step_2(self, p):
        '''navigation_step : ARROW identifier LSQBR identifier DOT phrase RSQBR'''
        p[0] = NavigationStepNode(key_letter=p[2],
                                  rel_id=p[4],
                                  phrase=p[6])
navigation_step : ARROW identifier LSQBR identifier DOT phrase RSQBR