在Python中使用字符串作为函数句柄

def add(a, b):
    return a + b

def subtract(a, b):
    return a - b

# 使用字符串调用函数
function_name = "add"
result = eval(function_name)(2, 3)
print(result)  # 输出：5

function_name = "subtract"
result = eval(function_name)(5, 2)
print(result)  # 输出：3

def add(a, b):
    return a + b

def subtract(a, b):
    return a - b

# 使用getattr()获取函数对象
function_name = "add"
function = getattr(__main__, function_name)
result = function(2, 3)
print(result)  # 输出：5

function_name = "subtract"
function = getattr(__main__, function_name)
result = function(5, 2)
print(result)  # 输出：3