python之如何简化这种Python代码

我有很多这样的代码块:

try: 
  a = get_a() 
  try: 
    b = get_b() 
 
    # varying codes here, where a and b are used 
 
  finally: 
    if b: 
      cleanup(b) 
finally: 
  if a: 
    cleanup(a) 

我希望写一些像这样的神奇代码:

some_magic: 
  # varying codes here, where a and b are also available 

这可能吗？

请您参考如下方法:

如果您不能或不想为a 和b 实现上下文协议(protocol)，您可以使用contextlib。制作上下文的设施:

from contextlib import contextmanager 
 
@contextmanager 
def managed(a): 
    try: 
        yield a 
    finally: 
        if a: 
            cleanup(a) 
 
with managed(get_a()) as a, managed(get_b()) as b: 
    # do something here 
    pass