py-execute-line misses temporary file

Environment:

Aquamacs 3.2 GNU Emacs 24.4.51.2
python-mode Version: 20160620.33 (elpa)
Python 2.7.12 |Continuum Analytics, Inc.| (default, Jun 29 2016, 11:09:23)

Running python locally on local files, no tramp-mode involved.

Symptoms:

I have basically never seen python-mode actually work. Instead I See two different behaviors, neither of them good.

When I invoke 'M-x py-execute-line' to send a single line of innocuous python code to the interpreter, the python interpreter starts in another window, the minbuffer shows "Wrote /var/folders/n1/tt80zjxj3sg3r4syxrnsd2n80000gn/T/python-22765Ls2.py", but nothing gets sent to the interpreter.

If instead of invoke Python -> Send -> Execute Line, I get the message "Wrote ..." with the temporary filename, and then the the interpreter frame belches up,

>>> Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
IOError: [Errno 2] No such file or directory: '/var/folders/n1/tt80zjxj3sg3r4syxrnsd2n80000gn/T//python-22765kUY.py'

Any suggestions for debugging this?
I have checked that the directory /var/folders/n1/tt80zjxj3sg3r4syxrnsd2n80000gn/T exists and is writable. While there are some files there, the temporary python file is not.