python3 datetime模块

from datetime import datetime

# 当前系统时间
d = datetime.now()
print(d)  # 2019-11-22 21:20:09.586674

2019-11-22 21:27:17.842169

from datetime import datetime

# 格林尼治时间，和我们相差8小时,utc协调世界时 Coordinated Universal Time
# coordinated 协调的
# universal 通用的
d1 = datetime.utcnow()
print(d1)

2019-11-22 13:27:33.084041

from datetime import datetime

# 用指定的时间创建datetime
d2 = datetime(2018, 2, 8, 12, 8, 8, 8886)
print(d2)

2018-02-08 12:08:08.008886

from datetime import datetime

# 时间格式化
d = datetime.now()
print(d)  # 2019-11-22 21:47:24.393180
print(type(d))  # <class 'datetime.datetime'>
s = d.strftime("%Y-%m-%d %H:%M:%S")
print(s)  # 2019-11-22 21:47:24

d = datetime.now().strftime("%Y-%m-%d %H:%M:%S")
print(d)  # 2019-11-22 21:47:24

2019-11-22 21:47:24.393180
<class 'datetime.datetime'>
2019-11-22 21:47:24
2019-11-22 21:47:24

from datetime import datetime

# 字符串转化成时间
str_date = input("请输入一个时间（格式 yyyy-mm-dd HH:MM:SS）:")
d = datetime.strptime(str_date, "%Y-%m-%d %H:%M:%S")
print(d)
print(type(d))

请输入一个时间（格式 yyyy-mm-dd HH:MM:SS）:2019-11-22 12:22:22
2019-11-22 12:22:22
<class 'datetime.datetime'>

from datetime import datetime

# 计算时间差
d1 = datetime(2019, 11, 22, 12, 22 , 22)
d2 = datetime(2019, 11, 21, 12, 22, 22)
diff = d1 - d2
print(diff.seconds)  # 单纯从时分秒来计算
print(diff.total_seconds())  # 包括年月日计算

0
86400.0