Pytest Style: test_deprecated.py

[utkbansal]

Fixes #

Changes made in this Pull Request:

PR Checklist

• Tests?
• Docs?
• CHANGELOG updated?
• Issue raised/referenced?

[richardjgowers]

maybe we should use pytest.fail here?

[jbarnoud]

Couldn't all of these test move to one parametrized function?

Something in the lines of (from the top of my head, not even typed somewhere I could execute it):

@pytest.mark.parametrize('module', (
    'MDAnalysis.core.units',
    'MDAnalysis.core.util',
    'MDAnalysis.core.log',
    ...)
def test_import(module):
    try:
        importlib.import_module(module)
    except ImportError:
        raise AssertionError("{} not available".format(module))

[kain88-de]

Please address the requested changes from @richardjgowers and @jbarnoud