Is there some special meaning to `[foo]` right after `from bar import foo` in python? (perhaps python2 specific)

Question

In particular, I am looking at this code:

import sqlite3
from sqlite3 import IntegrityError
[IntegrityError]

and am wondering: Is there some special meaning to [IntegrityError] ?

IntegrityError is just a class defined in the sqlite3 package, and of course, my own interpretation is that [IntgrityError] would just be an expression that puts it in a list, yet there I have it in a piece of code that I am studying. Could it be a typo? or am I missing some magic syntactic-sugar interpretation?

Answer 1

from sqlite3 import IntegrityError可以确保系统上已安装from sqlite3 import IntegrityError DB-API 2.0（PEP-249）版本，并且后续行[IntegrityError]抑制了linter。