How to Fix NameError: The OS Module Is Not Defined in Python

The os module is an integral part of the world of Python programming, and it provides functions and dependencies that enable us to interact with the Operating System.

If the os module functions are utilized without importing the os module first, it leads to an error, namely, the NameError: the OS module is not defined in Python.

This tutorial aims to provide a solution to prevent the NameError: the OS module is not defined in Python error.

Import the os Module to Fix NameError: the OS module is not defined in Python

Here is an example code where we use the os module’s functions without importing it first.

We try to use a function from the os module, namely, the getcwd() function, which is used to return the current directory in which the user works.

x = os.getcwd()
print(x)

The above code provides the following output:

Traceback (most recent call last):
  File "/tmp/sessions/a1f5d543b4798b53/main.py", line 2, in <module>
    x = os.getcwd()
NameError: name 'os' is not defined

We must import the os module before using any of its functions to prevent this error. For example, the following code imports the os module to resolve the NameError: the OS module is not defined in Python error.

import os

x = os.getcwd()
print(x)

The above code provides the following output:

/tmp/sessions/fe77fbcc369bc629

We must ensure that the os module is imported at a global scope instead of a local or nested scope. If the latter happens, we can only use the os module functions under a specific local scope.

Globally importing it enables us to use the functions provided by the os module throughout the length of the scope.