如何从pycparser生成的ast中找到switch语句？

from pycparser import c_parser, c_ast

class SwitchVisitor(c_ast.NodeVisitor):
    def visit_Switch(self, node):
        # 获取switch语句的条件表达式
        condition = node.cond
        print("Switch语句的条件表达式：", condition)

        # 获取switch语句的case语句
        for case in node.stmt.block_items:
            if isinstance(case, c_ast.Case):
                print("Switch语句的case语句：", case)

# 解析C代码并生成AST
parser = c_parser.CParser()
ast = parser.parse("""
    void test() {
        int num = 2;
        switch (num) {
            case 1:
                printf("Case 1");
                break;
            case 2:
                printf("Case 2");
                break;
            default:
                printf("Default case");
                break;
        }
    }
""")

# 遍历AST并找到switch语句
visitor = SwitchVisitor()
visitor.visit(ast)

Switch语句的条件表达式： <pycparser.c_ast.ID object at 0x7f8a4c0e4a90>
Switch语句的case语句： <pycparser.c_ast.Case object at 0x7f8a4c0e4b50>
Switch语句的case语句： <pycparser.c_ast.Case object at 0x7f8a4c0e4b90>
Switch语句的case语句： <pycparser.c_ast.Default object at 0x7f8a4c0e4bd0>