gistfile1.py

def prune(f):
    def wrapper(*args):
        def wrapped(*args):
            if wrapper.min:
                print("wrapper.min is true")
            else:
                print("wrapper.min is false")
            if random.random() > 0.5:
                # recurse
                return wrapped(*args)
            else:
                return True
        wrapper.min = True
        return wrapped(*args)
    return wrapper
    
import random  # after it's used in the inner function
               # just to show off the difference between definition and execution
               
@prune
def foo():
    # We never called this function, so who cares
    pass

foo()

output.txt

>>> foo()
wrapper.min is true
wrapper.min is true
wrapper.min is true
wrapper.min is true
True
>>> foo()
wrapper.min is true
True
>>> foo()
wrapper.min is true
True