de2.py

import ast

def menu(*args, **kwargs):
    def inner(f):
        pass
    return inner
    
a = ast.parse('''
@menu('xxx', parent='xxx')
class Xxx(object):
    pass
''')

for node in ast.walk(a):
    if type(node) == ast.ClassDef:
        for decorator in node.decorator_list:
            if d.func.id == 'menu':
                # do some thing with d
                pass