Recommend removing the gratuitous temporary variables. In this case, tests and bugform. Unnecessary temporaries clutter up the code and create 'line ordering dependencies' making changing the code harder and bug prone. Also helps avoid invoking code before it's needed - we might return the function due to some error before needing the value.
In this case, you could do: 
    'tests': testplan.testcases.filter(enabled=True),
    'bug_form': BugForm(initial={'reporter': request.user}),
(when a variable is created, but then only used once, it's generally better to remove it - in this method testplan is used multiple times, so it's not gratuitous)