Safe, minimal import sorting for Python projects.
μsort is a safe, minimal import sorter. Its primary goal is to make no “dangerous” changes to code. This is achieved by detecting distinct “blocks” of imports that are the most likely to be safely interchangeable, and only reordering imports within these blocks without altering formatting. Code style is left as an exercise for linters and formatters.
Within a block, µsort will follow common Python conventions for grouping imports based on source (standard library, third-party, first-party, or relative), and then sorting lexicographically within each group. This will commonly look like:
import re from pathlib import Path from typing import Iterable from unittest.mock import call, Mock, patch import aiohttp from aiosqlite import connect import foo from bar import bar from .main import main
Blocks are inferred from a number of real world conditions, including any intermediate statements between imports:
import warnings warnings.filterwarnings(...) import re import sys
In this case, µsort detects two blocks–separated by the call to
and will only sort imports inside of each block. Running µsort on this code
will generate no changes, because each block is already sorted.
Imports can be excluded from blocks using the
#usort:skip directive, or with
#isort:skip for compatibility with existing codebases. µsort will leave
these imports unchanged, and treat them as block separators.
See the User Guide for more details about how blocks are detected, and how sorting is performed.
µsort requires Python 3.6 or newer to run. Install µsort with:
$ pip install usort
To format one or more files or directories in-place:
$ usort format <path> [<path> ...]
To generate a diff of changes without modifying files:
$ usort diff <path>
To just validate that files are formatted correctly, like during CI:
$ usort check <path>
μsort is MIT licensed, as found in the LICENSE file.