>>> def demo():
...     text = "在函數(shù)內(nèi)部聲明了一個(gè)變量，這個(gè)變量就是局部變量"
...     print(text)
... 
>>> demo()
在函數(shù)內(nèi)部聲明了一個(gè)變量，這個(gè)變量就是局部變量
>>> print(text)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'text' is not defined

>>> def demo():
...     text = "在函數(shù)內(nèi)部聲明了一個(gè)變量，這個(gè)變量就是局部變量"
...     print(text)
... 
>>> text = "在函數(shù)外部創(chuàng)建了同名變量"
>>> demo()
在函數(shù)內(nèi)部聲明了一個(gè)變量，這個(gè)變量就是局部變量
>>> print(text)
在函數(shù)外部創(chuàng)建了同名變量

>>> def demo():
...     print(f"函數(shù)直接調(diào)用外部變量 [{text}]")
... 
>>> text = "在函數(shù)外部創(chuàng)建的變量"
>>> demo()
函數(shù)直接調(diào)用外部變量 [在函數(shù)外部創(chuàng)建的變量]

>>> def demo():
...     print(f"直接調(diào)用main中的變量: {text}")
... 
>>> # 此時(shí)main函數(shù)中并沒有text變量
>>> demo()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<stdin>", line 2, in demo
NameError: name 'text' is not defined

>>> global_var_1 = "這是一個(gè)全局變量"
>>> global_var_2 = ["這也是一個(gè)全局變量", 123]
>>> # 再定義一個(gè)函數(shù)和局部變量
>>> def demo(local_var_1, local_var_2):
...     local_var_3 = "這是一個(gè)局部變量"
...     local_var_4 = ("這也是一個(gè)局部變量", 456)
...     print(local_var_1)
...     print(local_var_2)
...     print(local_var_3)
...     print(local_var_4)
...     print("局部變量打印完畢")
... 
>>> demo(1, 2)  # 這里傳給函數(shù)的兩個(gè)形參是全局變量
1
2
這是一個(gè)局部變量
('這也是一個(gè)局部變量', 456)
局部變量打印完畢
>>> global_var_1
'這是一個(gè)全局變量'
>>> global_var_2
['這也是一個(gè)全局變量', 123]

def 函數(shù)名稱(形參1, 形參2, ...):
	# 1. 需在變量前使用關(guān)鍵字`global`進(jìn)行聲明，這樣一個(gè)全局變量就創(chuàng)建好了
	gloabl 全局變量名
	# 2. 聲明完畢后賦值
	全局變量名 = 值

# 3. 在調(diào)用函數(shù)之后，在函數(shù)中聲明的全局變量也就被創(chuàng)建了，否則不會(huì)創(chuàng)建的
函數(shù)名稱(傳參1，傳參2)

# 4. 可以任意使用那個(gè)全局變量了
print(全局變量)

>>> def demo():
...     # 聲明一個(gè)局部變量var_1
...     var_1 = "This is a local variable"
...     # 1. 先用global關(guān)鍵詞進(jìn)行全局變量的聲明
...     global var_2
...     # 2. 再對(duì)全局變量進(jìn)行賦值
...     var_2 = "This is a global variable"
...     print(f"[在函數(shù)內(nèi)使用] local_var: {var_1}")
...     print(f"[在函數(shù)內(nèi)使用] global_var: {var_2}")
... 
>>> demo()
[在函數(shù)內(nèi)使用] local_var: This is a local variable
[在函數(shù)內(nèi)使用] global_var: This is a global variable
>>> # 在main函數(shù)中調(diào)用函數(shù)生成的全局變量
>>> print(f"[在main函數(shù)中使用] global_var: {var_2}")
[在main函數(shù)中使用] global_var: This is a global variable

>>> def demo():
...     # 創(chuàng)建一個(gè)局部變量
...     var_1 = "局部變量123"
...     # 1. 先聲明是全局變量
...     global var_2
...     # 2. 再進(jìn)行賦值操作
...     var_2 = "全局變量456"
... 
>>> # 如果不調(diào)用函數(shù)直接使用在函數(shù)中生成的全局變量
>>> print(f"var_2: {var_2}")
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'var_2' is not defined
>>> # 必須先調(diào)用函數(shù)后，函數(shù)中的全局變量才能生成
>>> demo()
>>> print(f"var_2: {var_2}")
var_2: 全局變量456

>>> def demo():
...     # 如果聲明時(shí)直接賦值
...     global var_1 = "這是一個(gè)全局變量，但是在聲明時(shí)就賦值了"
  File "<stdin>", line 3
    global var_1 = "這是一個(gè)全局變量，但是在聲明時(shí)就賦值了"
                 ^
SyntaxError: invalid syntax

>>> def func_1():
...     global var_1
...     var_1 = "abc"
...     print(f"[function_1]全局變量var_1已經(jīng)創(chuàng)建: {var_1}")
... 
>>> def func_2():
...     global var_1
...     var_1 = "123"
...     print(f"[function_2]全局變量var_1已經(jīng)創(chuàng)建: {var_1}")
... 
>>> # 其實(shí)沒什么影響，和賦值的原理是一樣的
>>> # 先調(diào)用func_1
>>> func_1()
[function_1]全局變量var_1已經(jīng)創(chuàng)建: abc
>>> var_1
'abc'
>>> # 再調(diào)用func_2
>>> func_2()
[function_2]全局變量var_1已經(jīng)創(chuàng)建: 123
>>> var_1
'123'

>>> globals()
{'__name__': '__main__', '__doc__': None, '__package__': None, '__loader__': <class '_frozen_importlib.BuiltinImporter'>, '__spec__': None, '__annotations__': {}, '__builtins__': <module 'builtins' (built-in)>, 'demo': <function demo at 0x7ff433a520d0>, 'var_2': '全局變量456', 'func_1': <function func_1 at 0x7ff433a52280>, 'func_2': <function func_2 at 0x7ff433a52160>, 'var_1': '123'}

>>> print(globals()["var_2"])
全局變量456
>>> globals()["var_2"] = "對(duì)這個(gè)全局變量進(jìn)行重新賦值！"
>>> print(globals()["var_2"])
對(duì)這個(gè)全局變量進(jìn)行重新賦值！
>>> globals()
{'__name__': '__main__', '__doc__': None, '__package__': None, '__loader__': <class '_frozen_importlib.BuiltinImporter'>, '__spec__': None, '__annotations__': {}, '__builtins__': <module 'builtins' (built-in)>, 'demo': <function demo at 0x7ff433a520d0>, 'var_2': '對(duì)這個(gè)全局變量進(jìn)行重新賦值！', 'func_1': <function func_1 at 0x7ff433a52280>, 'func_2': <function func_2 at 0x7ff433a52160>, 'var_1': '123'}

>>> def demo(a, b):
...     c = 10  # 定義局部變量
...     global d  # 聲明全局變量
...     d = 100
...     print(locals())  # 查看該函數(shù)的局部變量
...     return a + b + c + d
... 
>>> # 定義一些全局變量
>>> aaa = 123
>>> bbb = 456
>>> # 查看全局變量
>>> globals()
{'__name__': '__main__', '__doc__': None, '__package__': None, '__loader__': <class '_frozen_importlib.BuiltinImporter'>, '__spec__': None, '__annotations__': {}, '__builtins__': <module 'builtins' (built-in)>, 'demo': <function demo at 0x7f1132cbd0d0>, 'aaa': 123, 'bbb': 456}
>>> # 查看局部變量
>>> locals()
{'__name__': '__main__', '__doc__': None, '__package__': None, '__loader__': <class '_frozen_importlib.BuiltinImporter'>, '__spec__': None, '__annotations__': {}, '__builtins__': <module 'builtins' (built-in)>, 'demo': <function demo at 0x7f1132cbd0d0>, 'aaa': 123, 'bbb': 456}
>>> # 調(diào)用函數(shù)
>>> demo(1, 2)
{'a': 1, 'b': 2, 'c': 10}
113
>>> # 查看全局變量
>>> globals()
{'__name__': '__main__', '__doc__': None, '__package__': None, '__loader__': <class '_frozen_importlib.BuiltinImporter'>, '__spec__': None, '__annotations__': {}, '__builtins__': <module 'builtins' (built-in)>, 'demo': <function demo at 0x7f1132cbd0d0>, 'aaa': 123, 'bbb': 456, 'd': 100}
>>> # 查看局部變量
>>> locals()
{'__name__': '__main__', '__doc__': None, '__package__': None, '__loader__': <class '_frozen_importlib.BuiltinImporter'>, '__spec__': None, '__annotations__': {}, '__builtins__': <module 'builtins' (built-in)>, 'demo': <function demo at 0x7f1132cbd0d0>, 'aaa': 123, 'bbb': 456, 'd': 100}

>>> class A:
...     def __init__(self, a, b, c):
...             self.a = a
...             self.b = b
...             self.c = c
...     name = "Leovin"
...     school = "xxx University"
... 
>>> print(f"vars(A): {vars(A)}")
vars(A): {'__module__': '__main__', '__init__': <function A.__init__ at 0x7fd201d5e160>, 'name': 'Leovin', 'school': 'xxx University', '__dict__': <attribute '__dict__' of 'A' objects>, '__weakref__': <attribute '__weakref__' of 'A' objects>, '__doc__': None}
>>> print(vars())
{'__name__': '__main__', '__doc__': None, '__package__': None, '__loader__': <class '_frozen_importlib.BuiltinImporter'>, '__spec__': None, '__annotations__': {}, '__builtins__': <module 'builtins' (built-in)>, 'A': <class '__main__.A'>}
>>> print(globals())
{'__name__': '__main__', '__doc__': None, '__package__': None, '__loader__': <class '_frozen_importlib.BuiltinImporter'>, '__spec__': None, '__annotations__': {}, '__builtins__': <module 'builtins' (built-in)>, 'A': <class '__main__.A'>}
>>> print(locals())
{'__name__': '__main__', '__doc__': None, '__package__': None, '__loader__': <class '_frozen_importlib.BuiltinImporter'>, '__spec__': None, '__annotations__': {}, '__builtins__': <module 'builtins' (built-in)>, 'A': <class '__main__.A'>}
>>> def func(a, b):
...     c = 1
...     global d
...     d = 10
...     return a + b + c + d
... 
>>> vars(func)
{}
>>> vars(func(1, 2))
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: vars() argument must have __dict__ attribute
>>> vars()
{'__name__': '__main__', '__doc__': None, '__package__': None, '__loader__': <class '_frozen_importlib.BuiltinImporter'>, '__spec__': None, '__annotations__': {}, '__builtins__': <module 'builtins' (built-in)>, 'A': <class '__main__.A'>, 'func': <function func at 0x7fd201d5e0d0>, 'd': 10}
>>> vars(A)
mappingproxy({'__module__': '__main__', '__init__': <function A.__init__ at 0x7fd201d5e160>, 'name': 'Leovin', 'school': 'xxx University', '__dict__': <attribute '__dict__' of 'A' objects>, '__weakref__': <attribute '__weakref__' of 'A' objects>, '__doc__': None})