bug#24762: 26.0.50; Spurious &optional in lisp/progmodes/python.el causes Edebug error

[Gemini Lasswell]

There's an &optional followed by &rest instead of a parameter name in
python-define-auxiliary-skeleton in lisp/progmodes/python.el. This
doesn't work with defmacro's Edebug spec and prevents use of Edebug on
the macro and testcover-start on the file.

To repro:
1. start Emacs at the top of its source tree, with -Q if you like
2. C-x C-f lisp/progmodes/python.el RET
3. C-s &optional &r RET
4. C-u C-M-x

Result: Invalid read syntax: "Bad argument:", &rest

In GNU Emacs 26.0.50.4 (x86_64-apple-darwin15.6.0, NS appkit-1404.47 Version 
10.11.6 (Build 15G1004))
 of 2016-10-20 built on rainbow.local
Repository revision: 9e1e257ea8605354d15b4bd93e0af6188aae40db
Windowing system distributor 'Apple', version 10.3.1404
Recent messages:
Guessed variable ’indent-tabs-mode’ (nil)
Guessed variable ’tab-width’ (8)
Could not guess variable ’c-basic-offset’ (Not a cc-mode)
Guessed variable ’nxml-child-indent’ (2)
Guessed variable ’css-indent-offset’ (2)
Guessed variable ’python-indent’ (2)
Mark saved where search started
edebug-syntax-error: Invalid read syntax: "Bad argument:", &rest
Configured using:
 'configure --with-ns --disable-ns-self-contained'

Configured features:
JPEG RSVG IMAGEMAGICK NOTIFY ACL GNUTLS LIBXML2 ZLIB TOOLKIT_SCROLL_BARS
NS

Important settings:
  value of $LANG: en_US.UTF-8
  locale-coding-system: utf-8-unix

Major mode: Emacs-Lisp

Minor modes in effect:
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  global-git-commit-mode: t
  async-bytecomp-package-mode: t
  global-undo-tree-mode: t
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  ivy-mode: t
  buffer-face-mode: t
  yas-global-mode: t
  yas-minor-mode: t
  pyvenv-mode: t
  shell-dirtrack-mode: t
  nameless-mode: t
  beacon-mode: t
  rainbow-mode: t
  column-enforce-mode: t
  volatile-highlights-mode: t
  region-state-mode: t
  ws-butler-global-mode: t
  ws-butler-mode: t
  show-smartparens-global-mode: t
  show-smartparens-mode: t
  smartparens-global-mode: t
  smartparens-global-strict-mode: t
  smartparens-strict-mode: t
  smartparens-mode: t
  which-key-mode: t
  modalka-mode: t
  recentf-mode: t
  global-auto-revert-mode: t
  auto-revert-mode: t
  winner-mode: t
  display-time-mode: t
  savehist-mode: t
  override-global-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  size-indication-mode: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t

Load-path shadows:
None found.

Features:
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font-lock syntax facemenu font-core term/tty-colors frame cl-generic
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korean japanese eucjp-ms cp51932 hebrew greek romanian slovak czech
european ethiopic indian cyrillic chinese charscript case-table epa-hook
jka-cmpr-hook help simple abbrev obarray minibuffer cl-preloaded nadvice
loaddefs button faces cus-face macroexp files text-properties overlay
sha1 md5 base64 format env code-pages mule custom widget
hashtable-print-readable backquote kqueue cocoa ns multi-tty
make-network-process emacs)

Memory information:
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 (symbols 48 59558 68)
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