Removing state pollution in zones

[sturmianseq]

This PR aims to improve test reliability of test test_pythonic by removing state pollution in python list zones by executing the test code with a deepcopy of zones.

The test can fail in this way if state pollution in zones is not removed:

        zonenames = [zone.Name for zone in zones]
>       assert printout == zonenames
E       AssertionError: assert ['PLENUM-1', ...PACE5-1', ...] == ['PLENUM-1', '...PACE5-1', ...]
E         At index 2 diff: 'SPACE2-1' != 'FIRST-SMALL-ZONE'
E         Full diff:
E         ['PLENUM-1',
E         'SPACE1-1',
E         -  'SPACE2-1',
E         +  'FIRST-SMALL-ZONE',
E         'SPACE3-1',...

[santoshphilip]

acknowledging your pull request.
I may take some time to get to this, as I am traveling now.

[sturmianseq]

No worries! Take your time:)