Don’t use a specific python instance, use whichever is first in the path.

script/generate_corelib.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 import re
 
 with open("corelib.wren", "r") as f:

script/generate_docs.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 import glob
 import markdown