error python uno & HTTPSConnection

Hi all

i'm facing a really strange problem

in a pyUNo module, i want to use
c = httplib.HTTPSConnection(host)

no problem, it works

but on a single win7 machine (at the moment), it fails telling
"AttributeError: 'module' object has no attribute 'HTTPSConnection'"

and effectivelly in my pyUNo script, a dir(httplib) does not show any 
HTTPS stuff

i know this is usually due to SSL support of python but

1- it is a standard libro3.5.4 installation that works on other win7

2- more strange, if i launch the libro python manually an try the c=.. 
line above then no problem; it works like a charm

so i'm lost here

anyone could tell me what could happen ? a win7 parameter ? (firewall, 
other ...)

thanks in advance

Laurent