Maintain support for pre-Python 3.11 (#1107)

Co-authored-by: C.A.M. Gerlach <[email protected]>

Author: hugovk

README.rst

@@ -21,9 +21,9 @@ nickname of "the devguide" by the Python core developers.
 
 The official home of this guide is https://devguide.python.org.
 
-Compilation
+Render HTML
 -----------
 
-For the compilation of the devguide, Python 3.11+ is needed::
+To render the devguide to HTML under ``_build/html``, run::
 
     make html

_tools/generate_release_cycle.py

@@ -5,6 +5,7 @@
 import csv
 import datetime as dt
 import json
+import sys
 
 import jinja2
 
@@ -44,7 +45,10 @@ def __init__(self) -> None:
 
     def write_csv(self) -> None:
         """Output CSV files."""
-        now_str = str(dt.datetime.now(dt.UTC))
+        if sys.version_info >= (3, 11):
+            now_str = str(dt.datetime.now(dt.UTC))
+        else:
+            now_str = str(dt.datetime.utcnow())
 
         versions_by_category = {"branches": {}, "end-of-life": {}}
         headers = None