[PYTHON] Variable scope when using internal functions

Nesting functions to use when you use it several times but you don't need to use it as a method for going out.

def hoge():
    def fuga():
        pass

I wondered what the handling of variables would be when using this, so I verified it.

Local variables

def hoge():
    x = 1
    def fuga():
        x = 3
    fuga()
    print(x)

Execution result

hoge()
1

In the case of local variables, it seems that they are treated as separate variables. Naturally natural. However, this can be changed with the nonlocal declaration.

def hoge():
    x = 1
    def fuga():
        nonlocal x
        x = 3
    fuga()
    print(x)

Execution result

hoge()
3

Class variables

class Sample:
    def __init__(self):
        self.hoge = None

def hoge():
    smp = Sample()
    smp.hoge = "abcde"
    def fuga():
        smp.hoge = "fghijk"
    fuga()
    print(amp.__dict__)

Execution result

hoge()
{'hoge': 'fghijk'}

I wonder if class variables will be treated globally.

bonus

You can use this to refresh your code when you want to put another value in a class variable depending on the condition

class Sample():
    def __init__(self):
        self.hoge = None
        self.fuga = None

def hoge(list):
    smp = Sample()
    def set_val(val1, val2):
        smp.hoge = val1
        smp.fuga = val2
    if len(list) == 1:
        set_val(list[0], None)
    else:
        set_val(list[0], list[1])
    print(smp.__dict__)

Execution result

hoge(['aaaa', 'bbbb'])
{'hoge': 'aaaa', 'fuga': 'bbbb'}

hoge(['cccc'])
{'hoge': 'cccc', 'fuga': None}

I don't know if there is any use for it!