PermissionError: [Errno 13] Permission denied: .... but only under normal user (not root)

Hi,
I've downloaded the electrum version 3.0.6-1 that is on Debian Stretch backports. There is no way to get it fired up under a normal user. The errors are below. The version of python installed on my system is 3.5.3-1. I find it strange that it fires up is i run "sudo electrum -v" but it doesn't if I don't. It's clearly a question of permissions but can't work out if this is a electrum issue of not. Any pointers?

Thanks

(base) [dom mag 27, 05:58 ][user@system1:~]electrum -v
Traceback (most recent call last):
File "/usr/bin/electrum", line 80, in
check_imports()
File "/usr/bin/electrum", line 64, in check_imports
import pbkdf2
File "", line 969, in _find_and_load
File "", line 958, in _find_and_load_unlocked
File "", line 673, in _load_unlocked
File "", line 669, in exec_module
File "", line 774, in get_code
File "", line 826, in get_data
PermissionError: [Errno 13] Permission denied: '/usr/local/lib/python3.5/dist-packages/pbkdf2.py'

Start with the /usr/bin/electrum entry point and the failing import of /usr/local/lib/python3.5/dist-packages/pbkdf2.py. Compare the file and directory permissions when running as the normal user versus root, then inspect how the Debian Stretch backport installs this dependency. Done means electrum -v starts successfully without sudo.