update doc/cmake.py - resolves import errors observed in sphinx 4.3.2

doc/cmake.py

@@ -2,6 +2,8 @@
 # file Copyright.txt or https://cmake.org/licensing for details.
 
 # Team SMNG note: This file comes from here: https://github.com/Kitware/CMake/blob/master/Utilities/Sphinx/cmake.py
+# Team SMNG note: applied patch from here: https://salsa.debian.org/science-team/ycm-cmake-modules/-/blob/master/debian/patches/fix-sphinx-build.patch
+#                 On Ubuntu 22.04 LTS I needed to additionally install the following package: python3-sphinxcontrib.qthelp
 
 import os
 import re
@@ -61,8 +63,12 @@ CMakeLexer.tokens["root"] = [
 
 # Monkey patch for sphinx generating invalid content for qcollectiongenerator
 # https://bitbucket.org/birkenfeld/sphinx/issue/1435/qthelp-builder-should-htmlescape-keywords
-from sphinx.util.pycompat import htmlescape
-from sphinx.builders.qthelp import QtHelpBuilder
+import html
+try:
+  from sphinxcontrib.qthelp import QtHelpBuilder
+except ImportError:
+  # sphinx < 4.0
+  from sphinx.builders.qthelp import QtHelpBuilder
 old_build_keywords = QtHelpBuilder.build_keywords
 def new_build_keywords(self, title, refs, subitems):
   old_items = old_build_keywords(self, title, refs, subitems)
@@ -71,7 +77,7 @@ def new_build_keywords(self, title, refs, subitems):
     before, rest = item.split("ref=\"", 1)
     ref, after = rest.split("\"")
     if ("<" in ref and ">" in ref):
-      new_items.append(before + "ref=\"" + htmlescape(ref) + "\"" + after)
+      new_items.append(before + "ref=\"" + html.escape(ref) + "\"" + after)
     else:
       new_items.append(item)
   return new_items