Skip to content
Related Articles

Related Articles

Improve Article

sys.path in Python

  • Difficulty Level : Easy
  • Last Updated : 01 Oct, 2020

Sys is a built-in Python module that contains parameters specific to the system i.e. it contains variables and methods that interact with the interpreter and are also governed by it. 

sys.path

sys.path is a built-in variable within the sys module. It contains a list of directories that the interpreter will search in for the required module. 

When a module(a module is a python file) is imported within a Python file, the interpreter first searches for the specified module among its built-in modules. If not found it looks through the list of directories(a directory is a folder that contains related modules) defined by sys.path.

Initializing sys.path 

There are three ways to specify a path :

  • DEFAULT- By default, the interpreter looks for a module within the current directory. To make the interpreter search in some other directory you just simply have to change the current directory. The following example depicts a default path taken by the interpreter:

Python3






# importing module
import sys
  
# printing all directories for 
# interpreter to search
sys.path

Output:

  • THROUGH ENVIRONMENT VARIABLES- An environment variable that contains the path an interpreter can take while looking for modules can be employed. Once set, it hints interpreter with directories to locate a module.  The following example shows how this can be done.
PYTHONPATH=C:\Users\Vanshi\Desktop

Python3




# importing module
import sys
  
# printing all directories
sys.path

Output:

  • APPENDING PATH- append() is a built-in function of sys module that can be used with path variable to add a specific path for interpreter to search. The following example shows how this can be done.

Python3




# importing module
import sys
  
# appending a path
sys.path.append('C:/Users/Vanshi/Desktop')
  
# printing all paths
sys.path

Output:

Note that the first string returned by path is always empty this is to indicate the interpreter to check in the current directory.

 Attention geek! Strengthen your foundations with the Python Programming Foundation Course and learn the basics.  

To begin with, your interview preparations Enhance your Data Structures concepts with the Python DS Course. And to begin with your Machine Learning Journey, join the Machine Learning – Basic Level Course




My Personal Notes arrow_drop_up
Recommended Articles
Page :