gistfile1.py

def works_fine(value=""):
    
    def closure():
        if not value:
            return "something"
        return value
    
    return closure



def does_not_work(value=""):
    
    def closure():
        if not value:
            value = "something"
        return value
    
    return closure



# Prints "something"
print works_fine()()

# Should also print "something"?
print does_not_work()()
        

gistfile2.txt

something
Traceback (most recent call last):
  File "/home/epeli/ohjelmointi/Subuser/subssh/poista.py", line 36, in <module>
    print does_not_work()()
  File "/home/epeli/ohjelmointi/Subuser/subssh/poista.py", line 24, in closure
    if not value:
UnboundLocalError: local variable 'value' referenced before assignment