While improving python 3 compatibility, fix whitespaces and remove the
useless try/except block as these modules are part of core.
Tested with Python 2.5.6, 2.6.6, 2.7.9, 3.2.6, 3.4.3 (with "make"
replaced by "true" and by comparing stdout).
Change-Id: I9c585da89aef76f01672c8f7320ac4a13c6cc7d7
Reviewed-on: https://code.wireshark.org/review/7790
Reviewed-by: Martin Mathieson <martin.r.mathieson@googlemail.com>