Imports are generally sorted alphabetically and described in various places besides PEP 8.
Alphabetically sorted modules are quicker to read and searchable. After all, Python is all about readability. Also, it is easier to verify that something is imported, and avoids duplicate imports.
There is nothing available in PEP 8 regarding sorting. So it's all about choosing what you use.
According to few references from reputable sites and repositories, also popularity, Alphabetical ordering is the way.
for e.g. like this:
import httplib
import logging
import random
import StringIO
import time
import unittest
from nova.api import openstack
from nova.auth import users
from nova.endpoint import cloud
OR
import a_standard
import b_standard
import a_third_party
import b_third_party
from a_soc import f
from a_soc import g
from b_soc import d
Reddit official repository also states that In general PEP-8 import ordering should be used. However, there are a few additions which are that for each imported group the order of imports should be:
import <package>.<module> style lines in alphabetical order
from <package>.<module> import <symbol> style in alphabetical order
References:
- https://code.google.com/p/soc/wiki/PythonStyleGuide
- https://github.com/reddit/reddit/wiki/PythonImportGuidelines
- http://docs.openstack.org/developer/hacking/
- http://developer.plone.org/reference_manuals/external/plone.api/contribute/conventions.html#grouping-and-sorting
PS: the isort utility automatically sorts your imports.