Python SSH script won't work while executed by PHP - php

Question

I have a Python (2.7) script that connect to a remote device through SSH and configure it.
This script works fine when I run it.
I have a PHP page that execute other Python scripts and they are also working fine.
The problem: the SSH script doesn't work when I'm running it from the PHP page.
(there is no problem with the PHP page nor the Python script)
To be more specific, the script (when executed by PHP) is running until it gets to the first SSH related code (import paramiko).
How can it be, and is there anything I can do to make it work?
Thanks!
(OS: windows XP. Server:Wamp (Apachi http server)
for example, consider this simple code:
fp=open("file.txt","w")
fp.write("text")
import paramiko
fp.write("another text")
fp.close()
if executed by me, everything works fine. If by the PHP page- only the code until "import paramiko" is executed.
or:
fp=open("file.txt","w")
fp.close()
import paramiko
fp2=open("file2.txt","w")
fp2.close()
Executed by me- both files created. by php- only the first.
Moreover: I tried using Try & Catch but nothing comes up. No exception is thrown.

Answer 1

My guess is that paramiko is not in your PYTHONPATH environmental variable for the Apache user.
When Apache fires up PHP, it is calling PHP as the whatever the "Apache" user happens to be (in Linux normally apache (or httpd) user in group www-data). Sometimes this user will have different environment variables set than the ones that users normally have. While this generally doesn't matter, sometimes it will cause bizarre interactions (and I can see it happening with Pip).
I would add a try... except around paramiko:
try:
import paramiko
except Exception as e:
# log your exception here.
pass # I put this here so the example can compile.
#rest of the script
That should let you know whether or not it is installed (and I suspect it isn't).