A new section has been added to the page as a result of https://bugs.python.org/issue37826. The change: https://github.com/python/cpython/commit/dcfe111eb5602333135b8776996332a8dcf59392

The wording it uses (in the beginning of section 8.5), defines chaining as setting __cause__ attribute in an exception, and later states that "Exception chaining happens automatically when an exception is raised inside an exception handler or finally section". This may lead the reader to a wrong idea that re-raising an exception without "from" in "except" and "finally" automatically sets __cause__. In reality it sets only __context__ attribute, which is similar concept to __cause__, but work a bit differently, as explained in library/exceptions.rst. I suggest to mention that difference and provide a link to the main article.