Speed up import rlcompleter by deferring inspect and re

rlcompleter imports inspect and re at module scope, but neither is needed to import the module or to construct a Completer. Each is used in exactly one completion method:

• inspect: only in Completer._callable_postfix
• re: only in Completer.attr_matches

inspect in particular is a heavy import: it transitively pulls in dis, tokenize, and more. Because rlcompleter is imported during interactive startup (to set up tab completion via readline), this import cost is paid on every interactive session and every import rlcompleter, even though the completion methods may never run.

Linked PRs

• gh-156364

まず rlcompleter モジュールと、issue で挙げられているエントリポイント Completer._callable_postfix および Completer.attr_matches から始めてください。変更前後の import の動作を検証し、rlcompleter の import 時に未使用の依存関係のためのコストがかからなくなっても、補完の動作が引き続き正しいことを確認してください。