Make a function decorator

I want to create a decorator (with tag) that performs pre / post processing of the function as shown below and reuse it.

>>> @MyDecorator('any-tag')
... def foo():
...     print u'foo'
... 
>>> foo():

pre-action. tag=any-tag.
foo
post-action. tag=any-tag.

Make it like this.

class MyDecorator(object):
    
    def __init__(self, tag):
        self._tag = tag
    
    def __call__(self, f0):
        def decorated(*args, **kwargs):
            print u'pre-action. tag=' + self._tag
            ret = f0(*args, **kwargs)
            print u'post-action. tag=' + self._tag
            return ret
        return decorated

Version using functools.wraps.

Thank you @termoshtt (^ ◇ ^)

from functools import wraps

def MyDecorator(tag):
    def dec(f0):
        @wraps(f0)
        def decorated(*args, **kwargs):
            print u'pre-action. tag=' + tag
            ret = f0(*args, **kwargs)
            print u'post-action. tag=' + tag
            return ret
        return decorated
    return dec

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