You can use datetime.date.today() and convert the resulting datetime.date object to a string:

from datetime import date
today = str(date.today())
print(today)   # '2017-12-26'

#python3

import datetime
print(
    '1: test-{date:%Y-%m-%d_%H:%M:%S}.txt'.format( date=datetime.datetime.now() )
    )

d = datetime.datetime.now()
print( "2a: {:%B %d, %Y}".format(d))

# see the f" to tell python this is a f string, no .format
print(f"2b: {d:%B %d, %Y}")

print(f"3: Today is {datetime.datetime.now():%Y-%m-%d} yay")

#4: to make the time timezone-aware pass timezone to .now()
tz = datetime.timezone.utc
ft = "%Y-%m-%dT%H:%M:%S%z"
t = datetime.datetime.now(tz=tz).strftime(ft)
print(f"4: timezone-aware time: {t}")

1: test-2018-02-14_16:40:52.txt

2a: March 04, 2018

2b: March 04, 2018

3: Today is 2018-11-11 yay

4: timezone-aware time: 2022-05-05T09:04:24+0000

Description:

Using the new string format to inject value into a string at placeholder {}, value is the current time.

Then rather than just displaying the raw value as {}, use formatting to obtain the correct date format.

https://docs.python.org/3/library/string.html#formatexamples

https://docs.python.org/3/library/datetime.html

Here is how you can accomplish the same using python's general formatting function...

>>>from datetime import datetime
>>>"{:%B %d, %Y}".format(datetime.now())

The formatting characters used here are the same as those used by strftime. Don't miss the leading : in the format specifier.

Using format() instead of strftime() in most cases can make the code more readable, easier to write and consistent with the way formatted output is generated...

>>>"{} today's date is: {:%B %d, %Y}".format("Andre", datetime.now())

Compare the above with the following strftime() alternative...

>>>"{} today's date is {}".format("Andre", datetime.now().strftime("%B %d, %Y"))

Moreover, the following is not going to work...

>>>datetime.now().strftime("%s %B %d, %Y" % "Andre")
Traceback (most recent call last):
  File "<pyshell#11>", line 1, in <module>
    datetime.now().strftime("%s %B %d, %Y" % "Andre")
TypeError: not enough arguments for format string

And so on...