global vs nonlocal in Python (2)

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*Memo:

• My post explains global and nonlocal with 3 functions (1).
• My post explains global and nonlocal with 3 functions (3).

A nonlocal statement can refer to a non-local variable as shown below:

<Read(Intuitive version)>:

""" It's from the viewpoint of `third()` """

num = 2 # <- ✖
def first():
    num = 3 # <- ✖
    def second():
        num = 4 # <- 〇
        def third():
            nonlocal num # Here
            print(num) # 4
        third()
    second()
first()

""" It's from the viewpoint of `third()` """

num = 2 # <- ✖
def first():
    num = 3 # <- 〇
    def second():
        # num = 4 # <- Commented
        def third():
            nonlocal num # Here
            print(num) # 3
        third()
    second()
first()

""" It's from the viewpoint of `third()` """

num = 2 # <- ✖
def first():
    # num = 3 # <- Commented
    def second():
        # num = 4 # <- Commented
        def third():
            nonlocal num # SyntaxError: no binding
            print(num)   # for nonlocal 'num' found
        third()
    second()
first()

<Read(Unintuitive version)>:

""" It's from the viewpoint of `third()` """

def first():
    def second():
        def third():
            nonlocal num # Here
            print(num) # 4
        num = 4 # <- 〇
        third()
    num = 3 # <- ✖
    second()
num = 2 # <- ✖
first()

""" It's from the viewpoint of `third()` """

def first():
    def second():
        def third():
            nonlocal num # Here
            print(num) # 3
        # num = 4 # <- Commented
        third()
    num = 3 # <- 〇
    second()
num = 2 # <- ✖
first()

""" It's from the viewpoint of `third()` """

def first():
    def second():
        def third():
            nonlocal num # SyntaxError: no binding
            print(num)   # for nonlocal 'num' found
        # num = 4 # <- Commented
        third()
    # num = 3 # <- Commented
    second()
num = 2 # <- ✖
first()

<Change(Intuitive version)>:

""" It's from the viewpoint of `third()` """

num = 2 # <- ✖
def first():
    num = 3 # <- ✖
    def second():
        num = 4 # <- 〇
        def third():
            nonlocal num # Here
            num += 10    # Here
            print(num) # 14
        third()
        print(num) # 14
    second()
first()

""" It's from the viewpoint of `third()` """

num = 2 # <- ✖
def first():
    num = 3 # <- 〇
    def second():
        # num = 4 # <- Commented
        def third():
            nonlocal num # Here
            num += 10    # Here
            print(num) # 13
        third()
        print(num) # 13
    second()
first()

""" It's from the viewpoint of `third()` """

num = 2 # <- ✖
def first():
    # num = 3 # <- Commented
    def second():
        # num = 4 # <- Commented
        def third():
            nonlocal num # SyntaxError: no binding
            num += 10    # for nonlocal 'num' found
            print(num)
        third()
        print(num) 
    second()
first()

<Change(Unintuitive version)>:

""" It's from the viewpoint of `third()` """

def first():
    def second():
        def third():
            nonlocal num # Here
            num += 10    # Here
            print(num) # 14
        num = 4 # <- 〇
        third()
        print(num) # 14
    num = 3 # <- ✖
    second()
num = 2 # <- ✖
first()

""" It's from the viewpoint of `third()` """

def first():
    def second():
        def third():
            nonlocal num # Here
            num += 10    # Here
            print(num) # 13
        # num = 4 # <- Commented
        third()
        print(num) # 13
    num = 3 # <- 〇
    second()
num = 2 # <- ✖
first()

""" It's from the viewpoint of `third()` """

def first():
    def second():
        def third():
            nonlocal num # SyntaxError: no binding
            num += 10    # for nonlocal 'num' found
            print(num)
        # num = 4 # <- Commented
        third()
        print(num)
    # num = 3 # <- Commented
    second()
num = 2 # <- ✖
first()