您可以使用 datetime。组合（日期，时间）;在这段时间内，您创建一个初始化为午夜的 datetime.time 对象。

  from datetime import date 
 from datetime import datetime 
d = date.today（）
 datetime.combine（d，datetime.min.time（））
 

Silly question, but is there a built-in method for converting a date to a datetime in Python, ie. getting the datetime for the midnight of the date? The opposite conversion is easy - datetime has a .date() method. Do I really have to manually call datetime(d.year, d.month, d.day) ?

You can use datetime.combine(date, time); for the time, you create a datetime.time object initialized to midnight.

from datetime import date
from datetime import datetime
d = date.today()
datetime.combine(d, datetime.min.time())