why is this failing?

[Skip Montanaro]

    John> Just to check (I'm using a patched version, so it's a bit of a
    John> pain to switch): the latest versions from the python-mode SF
    John> project highlight builtins like "len" and "list", not just
    John> keywords like "print"?

I'm running 4.38.  Here are the keywords it knows about:

    "and"      "assert"   "break"   "class"
    "continue" "def"      "del"     "elif"
    "else"     "except"   "exec"    "for"
    "from"     "global"   "if"      "import"
    "in"       "is"       "lambda"  "not"
    "or"       "pass"     "print"   "raise"
    "return"   "while"    "yield"

So, no, the builtins are not colored, just the keywords.  You could easily
extend the list though.

Skip