How to create a file name with the current date & time in Python?

Question

Here is a functional code (create file with success)

sys.stdout = open(\'filename1.xml\', \'w\')

Now I\'m trying to name the file with the cu

Answer 1

Change this line

filename1 = datetime.now().strftime("%Y%m%d-%H%M%S")

To

filename1 = datetime.datetime.now().strftime("%Y%m%d-%H%M%S")

Note the extra datetime. Alternatively, change your import datetime to from datetime import datetime

Answer 2

now is a class method in the class datetime in the module datetime. So you need

datetime.datetime.now()

Or you can use a different import

from datetime import datetime

Done this way allows you to use datetime.now as per the code in the question.

Answer 3

I'm surprised there is not some single formatter that returns a default (and safe) 'for appending in filename' - format of the time, We could simply write FD.write('mybackup'+time.strftime('%(formatter here)') + 'ext'

"%x" instead of "%Y%m%d-%H%M%S"

Answer 4

While not using datetime, this solves your problem (answers your question) of getting a string with the current time and date format you specify:

import time
timestr = time.strftime("%Y%m%d-%H%M%S")
print timestr

yields:

20120515-155045

so your filename could append or use this string.

Answer 5

This one is much more human readable.

from datetime import datetime

datetime.now().strftime("%Y_%m_%d-%I_%M_%S_%p")

'2020_08_12-03_29_22_AM'

Answer 6

Here's some that I needed to include the date-time stamp in the folder name for dumping files from a web scraper.

# import time and OS modules to use to build file folder name
import time
import os 

# Build string for directory to hold files
# Output Configuration
#   drive_letter = Output device location (hard drive) 
#   folder_name = directory (folder) to receive and store PDF files

drive_letter = r'D:\\' 
folder_name = r'downloaded-files'
folder_time = datetime.now().strftime("%Y-%m-%d_%I-%M-%S_%p")
folder_to_save_files = drive_letter + folder_name + folder_time 

# IF no such folder exists, create one automatically
if not os.path.exists(folder_to_save_files):
    os.mkdir(folder_to_save_files)