How to run os.mkdir() with -p option in Python?

According to the documentation, you can now use this since python 3.2

os.makedirs("/directory/to/make", exist_ok=True)

and it will not throw an error when the directory exists.

Something like this:

if not os.path.exists(directory_name):
    os.makedirs(directory_name)

UPD: as it is said in a comments you need to check for exception for thread safety

try:
    os.makedirs(directory_name)
except OSError as err:
    if err.errno!=17:
        raise

You can try this:

# top of the file
import os
import errno

# the actual code
try:
    os.makedirs(directory_name)
except OSError as exc: 
    if exc.errno == errno.EEXIST and os.path.isdir(directory_name):
        pass