Absolute and Relative Imports in Python

In Python, when you need to access code from another file or package, you use import statements. There are two approaches − absolute imports (full path from the project root) and relative imports (path relative to the current file).

How Python Resolves Imports

When Python encounters an import statement, it searches in this order −

• Module cache − Checks sys.modules for previously imported modules.
• Built-in modules − Searches Python's standard library.
• sys.path − Searches directories in sys.path (current directory first).
• If not found anywhere, raises ModuleNotFoundError.

Import Order Convention

Import statements should be at the top of the file in this order −

# 1. Standard library
import os
import sys

# 2. Third-party packages
import requests
import numpy

# 3. Local application imports
from mypackage import mymodule

Project Structure

Consider this project layout for the examples below −

my_project/
??? packageA/
?   ??? __init__.py
?   ??? moduleA1.py
?   ??? moduleA2.py      # contains myfunc()
??? packageB/
?   ??? __init__.py
?   ??? moduleB1.py
??? main.py

Absolute Import

Specifies the full path from the project root using dots as separators ?

# In main.py ? import myfunc from packageA/moduleA2.py
from packageA.moduleA2 import myfunc

# Other absolute import styles
import packageA.moduleA1
from packageA import moduleA2

The path starts from the project root and traces down to the target module. A dot (.) replaces the slash (/) in the directory path.

Relative Import

Specifies the path relative to the current file's location. A single dot (.) means the current package, two dots (..) means one level up ?

# In packageB/moduleB1.py ? import moduleA1 from packageA
from ..packageA import moduleA1

# In packageA/moduleA1.py ? import from same package
from . import moduleA2
from .moduleA2 import myfunc

The .. in the first example means: go up one directory from packageB/ to my_project/, then into packageA/.

Comparison

Conclusion

Use absolute imports as the default (clearer, PEP 8 recommended). Use relative imports within the same package for shorter paths that survive project relocation. Always place import statements at the top of the file in the order: standard library, third-party, then local.