Try bumping to 3.8

.github/workflows/core-tests.yml

@@ -10,7 +10,7 @@ jobs:
       matrix:
         # This range ensures coding standard does not conflict with 
         #  changes in newer Pythons
-        python-version: [3.7, 3.8, 3.9, "3.10"]
+        python-version: [3.8, 3.9, "3.10"]
 
     steps:
     - uses: actions/checkout@v3

piku.py

@@ -4,9 +4,9 @@
 
 try:
     from sys import version_info
-    assert version_info >= (3, 7)
+    assert version_info >= (3, 8)
 except AssertionError:
-    exit("Piku requires Python 3.7 or above")
+    exit("Piku requires Python 3.8 or above")
 
 from importlib import import_module
 from collections import defaultdict, deque