平时我们使用+-*、来实现加法减少乘法除法，用><=来 实现比较 操作，其实在Python中这些运算符都有对应 的函数替代写法。

operator 模块包含的方法

 
import operator 
a =1
b =3 
result =  operator.lt(a, b)
print(result)
result =     operator.le(a, b)
print(result)
result =     operator.eq(a, b)
print(result)
result =     operator.ne(a, b)
print(result)
result =     operator.ge(a, b)
print(result)
result =    operator.gt(a, b)
print(result)
result =    operator.__lt__(a, b)
print(result)
result =   operator.__le__(a, b)
print(result)
result =    operator.__eq__(a, b)
print(result)
result =    operator.__ne__(a, b)
print(result)
result =    operator.__ge__(a, b)
print(result)
result =    operator.__gt__(a, b)
print(result)

True
True
False
True
False
False
True
True
False
True
False
False

比较两个列表：

# 导入 operator 模块
import operator
a = [1, 2]
b = [2, 3]
c = [2, 3]
print("operator.eq(a,b): ", operator.eq(a,b))
print("operator.eq(c,b): ", operator.eq(c,b))

运算符函数

operator 模块提供了一套与 Python 的内置运算符对应的高效率函数。例如，operator.add(x, y) 与表达式 x+y 相同。

实际上平时很多运算符可以用对应的函数替换

接着我们写代码对比一下

>>> import operator
>>> operators = {
...     "+": operator.add,
...     "-": operator.sub,
...     "*": operator.mul,
...     "/": operator.truediv,
... }

>>> def perform_operation(op_string, number1, number2):
...     return operators[op_string](number1, number2)
...

>>> perform_operation("-", 10, 5)
5

也可以自己实现四则运算

>>> operators = {
...     "+": lambda a, b: a + b,
...     "-": lambda a, b: a - b,
...     "*": lambda a, b: a * b,
...     "/": lambda a, b: a / b,
... }

使用 methodcaller(调用对象的方法

>>> from dataclasses import dataclass

>>> @dataclass
... class Musician:
...     id: int
...     fname: str
...     lname: str
...     group: str
...
...     def get_full_name(self, last_name_first=False):
...         if last_name_first:
...             return f"{self.lname}, {self.fname}"
...         return f"{self.fname} {self.lname}"

调用 get_full_name方法的推优，不通过ojb.methondname()的方式

>>> import operator
>>> first_last = operator.methodcaller("get_full_name")
>>> for person in group_members:
...     print(first_last(person))
...
Brian Wilson
Carl Wilson
Dennis Wilson
Bruce Johnston
Hank Marvin
Bruce Welch

如果大家用过这种方式，其实有点像Java编程语言的反射