The Python Oracle

Local (?) variable referenced before assignment

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Chapters
00:00 Question
00:38 Accepted answer (Score 281)
01:17 Answer 2 (Score 64)
01:32 Answer 3 (Score 12)
01:46 Thank you

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Full question
https://stackoverflow.com/questions/1190...

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https://meta.stackexchange.com/help/lice...

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Tags
#python #python3x

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ACCEPTED ANSWER

Score 285


In order for you to modify test1 while inside a function you will need to do define test1 as a global variable, for example:

test1 = 0
def test_func():
    global test1 
    test1 += 1
test_func()

However, if you only need to read the global variable you can print it without using the keyword global, like so:

test1 = 0
def test_func():
    print(test1)
test_func()

But whenever you need to modify a global variable you must use the keyword global.



ANSWER 2

Score 65


Best solution: Don't use globals

>>> test1 = 0
>>> def test_func(x):
        return x + 1

>>> test1 = test_func(test1)
>>> test1
1


ANSWER 3

Score 12


You have to specify that test1 is global:

test1 = 0
def test_func():
    global test1
    test1 += 1
test_func()