Python Program to Safely Create a Nested Directory

There are different ways to create a nested directory depending on the versions of python you are using. For this example, we will create directories as shown in the image below.

Example 1: Using pathlib.Path.mkdir

For python 3.5 and above, you can use pathlib.Path.mkdir to create a nested directory.

from pathlib import Path
Path("/root/dirA/dirB").mkdir(parents=True, exist_ok=True)

• Import class Path from pathlib library.
• Call the module mkdir() with two arguments parents and exist_ok.
• By default, parents is set False. In this case, if the parent directory is not present, then FileNotFoundError is thrown. For example, if you want to create a nested directory /folder1/folder2/folder3, and folder1 (parent) does not exist already, then FileNotFoundError is raised by default. So, we set it to True.
• exist_ok is False by default. If the directory already exists, FileExistsError is raised. Set it to True to prevent this error.

Note: You should provide the full path (absolute path) of the directory (not relative path). If the directory already exists, the above code does not raise an exception.

Example 2: Using os.makedirs

For python 3.2 and above, you can use os.makedirs.

import os

os.makedirs("/root/dirA/dirB")

• Using method makedirs() from module os, a nested directory can be created in a simple way.
• The parameter passed is the nested directory we wanted to create.

You should provide the full path (absolute path) of the directory (not relative path). If the directory already exists, the above code does not raise an exception.

Example 3: Using distutils.dir_util

import distutils.dir_util

distutils.dir_util.mkpath("/root/dirA/dirB")

This example is also similar to Example 2. Here mkpath() is used instead of makedirs().

You should provide the full path (absolute path) of the directory (not the relative path). If the directory already exists, the above code does not raise an exception.

Example 4: Raising an exception if directory already exists

import os

try:
    os.makedirs("/dirA/dirB")
except FileExistsError:
    print("File already exists")

This example is similar to Example 2.

• The statement is put inside the try block.
• If the directory is already present, FileExistsError is caught by the except block and runs the statements inside the block.