postgres 9.5 create function plpthon3u resets connections to server

[Peter Crosbie <pjcrosbie@xxxxxxxxx>]

this is a repost of a message I mistakenly sent to pgslq-novice, although it is probably a simple question

I believe my issue may be that I don't have the correct python interpreter on the server's path. I couldn't find
the required version in the documents and determined what I thought was required by using dependency walker 

on the plpython3.dll in postgres lib/.

A pointer to more detailed doc or example would be great. Thanks.

Anyway, here is my issue:

postgresql 9.5 on windows 10, x64.

I have created the extension plpython3u with python 3.3.5 on the server's path and it appeared to create the extension successfully:

SELECT * FROM pg_available_extensions
WHERE name like '%python%' order by name;


       name        | default_version | installed_version |                  comment

-------------------+-----------------+-------------------+------------------------------------------
-
 hstore_plpython2u | 1.0             |                   | transform between hstore and plpython2u
 hstore_plpython3u | 1.0             |                   | transform between hstore and plpython3u
 hstore_plpythonu  | 1.0             |                   | transform between hstore and plpythonu
 ltree_plpython2u  | 1.0             |                   | transform between ltree and plpython2u
 ltree_plpython3u  | 1.0             |                   | transform between ltree and plpython3u
 ltree_plpythonu   | 1.0             |                   | transform between ltree and plpythonu
 plpython2u        | 1.0             |                   | PL/Python2U untrusted procedural language
 plpython3u        | 1.0             | 1.0               | PL/Python3U untrusted procedural language
 plpythonu         | 1.0             |                   | PL/PythonU untrusted procedural language
(9 rows)

However when I attempt to create the following function (from the pg docs)

CREATE FUNCTION pymax (a integer, b integer)
  RETURNS integer
AS $$
  if a > b:
    return a
  return b
$$ LANGUAGE plpython3u;

the psql (or pgadmin3) terminal's connection is reset.

The python 3.3 on the path is anaconda's distb and runs fine on its own. I couldn't find the required version of python in the postgresql docs and used dependency walker as described here Postgres database crash when installing plpython to find the required dll that plpython3.dll in the server's lib/ requires.

Can anyone help me with what I have missed?

This question is also posted on stackoverflow here. 

Thanks in advance for your help.

Many thanks