Pending removal in Python 3.18

• No longer accept a boolean value when a file descriptor is expected. (Contributed by Serhiy Storchaka in gh-82626.)

• decimal:

  • The non-standard and undocumented Decimal format specifier 'N', which is only supported in the decimal module’s C implementation, has been deprecated since Python 3.13. (Contributed by Serhiy Storchaka in gh-89902.)

• Deprecations defined by PEP 829:

  • import lines in name.pth files are silently ignored.

  (Contributed by Barry Warsaw in gh-148641.)

• http.client:

  • http.client.HTTPMessage.getallmatchingheaders() has been deprecated since Python 3.16. It has returned an empty list for every input since Python 3.0; use email.message.Message.get_all() instead. (Contributed by Julian Soreavis in gh-153648.)