replace python 3.11 with 3.12

Makefile

@@ -1,4 +1,4 @@
-python := "$(shell { command -v python3.11 || command -v python3 || command -v python || echo false; } 2>/dev/null)"
+python := "$(shell { command -v python3.12 || command -v python3 || command -v python || echo false; } 2>/dev/null)"
 
 # Set the relative path to installed binaries under the project virtualenv.
 # NOTE: Creating a virtualenv on Windows places binaries in the 'Scripts' directory.

README.md

@@ -73,7 +73,7 @@ The python code inside simplates is only for request-specific logic, common back
 
 Make sure you have the following dependencies installed first:
 
-- python ≥ 3.11
+- python ≥ 3.12
   - including the C headers of python and libffi, which are packaged separately in many Linux distributions
 - postgresql 16 (see [the official download & install docs](https://www.postgresql.org/download/))
 - make

cli/check-python-version.py

@@ -1,7 +1,7 @@
 import sys
 
-if sys.version_info < (3, 11, 0):
+if sys.version_info < (3, 12, 0):
-    print("Liberapay requires Python >= 3.11, but %s is version %s.%s" %
+    print("Liberapay requires Python >= 3.12, but %s is version %s.%s" %
           (sys.executable, sys.version_info[0], sys.version_info[1]))
     sys.exit(1)
 if sys.version_info >= (3, 13, 0):

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist = py311,py312
+envlist = py312
 skipsdist = True
 
 [testenv]