import datetime

print(datetime.datetime.now())
print(type(datetime.datetime.now()))

#2022-08-13 07:59:45.154989
#<class 'datetime.datetime'>

• year month day has no default argument

import datetime

x = datetime.datetime.now()
print(x)
# 2022-08-26 08:44:56.572730

y = datetime.datetime(2022, 5, 1)
print(y)
# 2022-05-01 00:00:00

print(y - x)
#-118 days, 15:14:27.176345

import datetime

x = datetime.datetime.now()

print(x.strftime("%A"))
print(x.strftime("%m"))

#Saturday
#08

Note

• 各種format code: https://docs.python.org/3/library/datetime.html#strftime-and-strptime-format-codes
• 實際運用 (系統監控): https://blog.51cto.com/u_13885935/2174962
• The difference between strftime and strptime:

https://blog.csdn.net/weixin_42139375/article/details/81105479

https://docs.python.org/3/library/datetime.html#strftime-strptime-behavior

import datetime

now = datetime.datetime.now()
oneday = datetime.datetime(2020, 1, 1)

diff = now - oneday

print(diff) #955 days, 8:17:59.628885
print(type(diff)) #<class 'datetime.timedelta'>

#timedelta read-only attribute/method
print(diff.days) #955
print(diff.total_seconds()) #82541994.795662

import datetime

now = datetime.datetime.now()
gap = datetime.timedelta(1)

tomorrow = now + gap
print(tomorrow)

#2022-08-14 08:22:41.225958

import datetime

now = datetime.datetime.now()
oneday = datetime.datetime(2020, 1, 1)

print(now == oneday)
print(now > oneday)
print(now < oneday)