Developer shares refactoring workflow combining ast-grep codemods with Claude Code

On October 18, 2026, a DEV Community article described a way of splitting a refactoring job between two tools. The author divided the work into two parts: calls that could be matched by pattern were handed to an ast-grep codemod for bulk replacement, while only the small number of files that required judgment were passed to Claude Code. The example given was rewriting Python's deprecated logger.warn calls to logger.warning. According to the article, this approach keeps the coding agent from reading files one by one and consuming context, and it avoids accidentally changing the similarly named warnings.warn. The piece notes that logger.warn() has been deprecated since Python 3.3, that CPython removed it on its main branch during the 3.13 cycle and then restored it with a one-line reason, "Keep the deprecated logging warn() method in Python 3.13," and that the current deprecations page still lists it as pending removal. The article does not report the size, duration, or results of the refactoring.