bug#50503: [PATCH] Properly encode all strings sent to the Python shell

[Augusto Stoffel]

Tags: patch

Some Python shell functions naively assume that '''<arbitrary text>'''
is valid Python code, which is not true, say, if the arbitrary text
ends with a quote sign.  This patch fixes this.

Some more remarks:

- python.el now depends on Emacs 28 because it uses 'format-prompt' and
  'comint-max-line-length' (luckily, only the latter is my fault).  Is
  this a problem?
- I've deleted some defcustoms which are not usable in my opinion.  The
  intended customizability is not impossible, but can only be achieved
  by advising certain functions.
- There are some long-obsolete functions (since say Emacs 24) that I
  would like to delete.  One example is 'python-send-string' which is
  easy to confuse with the 'python-shell-send-string', which is real
  deal.  What are the rules for this?

In GNU Emacs 28.0.50 (build 6, x86_64-pc-linux-gnu, GTK+ Version 3.24.29, cairo 
version 1.17.4)
 of 2021-09-09 built on toolbox
Repository revision: 8c023e5ea159c6756c92fd02643983aa449e0da9
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.12101002
System Description: Fedora 34 (Workstation Edition)

0001-Properly-encode-all-strings-sent-to-Python-shell.patch
Description: Text Data