Modules and Imports

A Python file is a module. Use import to use code from another file or the standard library.

Importing modules

python
import math
print(math.sqrt(16))  # 4.0

Import specific names:

python
from math import sqrt, pi
print(sqrt(16))

Import with alias:

python
import numpy as np

Your own modules

Create utils.py with functions. In another file in the same folder:

python
import utils
utils.some_function()
# or
from utils import some_function

Standard library

Python ships with many modules: os, sys, json, datetime, collections, itertools, etc. Use them to avoid reinventing the wheel.