如何访问map函数之外的变量？

def outer_function():
    variable = 10
    
    def inner_function(x):
        return x + variable
    
    return inner_function

closure = outer_function()
result = closure(5)  # 访问了外部函数的变量 variable
print(result)  # 输出 15

variable = 10

def map_function(x):
    return x + variable

result = map_function(5)  # 访问了全局变量 variable
print(result)  # 输出 15

def map_function(x, variable):
    return x + variable

variable = 10
result = map_function(5, variable)  # 将外部变量 variable 作为参数传递
print(result)  # 输出 15