1.通过math包

import math
print(math.e)

结果：

2.718281828459045

2.$$计算方法1:e=(1+\frac{1}{n}{)}^n$$

n=100000
e=(1+1/n)**n
print(e)

结果：

2.7182682371922975

3.$$计算方法2：e=\sum _{k=0}^n\frac{1}{k!}$$

def jiecheng(number):
    if number==1:
        return 1
    else:
        return number*jiecheng(number-1)
e=1
n=10
for i in range(1,n):
    e+=1/jiecheng(i)
print(e)

结果：

2.7182815255731922