datetime combines date and time. It has the methods date() and time() to get the corresponding date and time objects, and there's a handy combine function to combine date and time into a datetime.
from datetime import datetime
today= datetime.today()
if today.strftime('%Y-%m-%d') == other_datetime.strftime('%Y-%m-%d'):
print("same day as today: {0}".format(today.strftime('%Y-%m-%d')))