(p)
definition_unit_ : definition_unit ';'
                        | definition_unit
definition_unit_ : definition_unit ';'
                        | definition_unit
definition_unit_ : definition_unit ; | definition_unit
def p_definition_unit_(p):
    '''definition_unit_ : definition_unit ';'
                        | definition_unit'''
def p_definition_unit_ ( p ) :