human
I wrote the below code

    def _Apply(obj):
        if isinstance(obj, type):
            _ModifyClass(obj, (list(testcases) if (not isinstance(testcases, collections.Sequence)) else testcases), naming_type)
            return obj
        else:
            return _ParameterizedTestIter(obj, testcases, naming_type)
    if _IsSingletonList(testcases):
        assert _NonStringIterable(testcases[0]), 'Single    parameter    argument    must    be    a    non-string    iterable'
        testcases = testcases[0]
    return _Apply

What's a good function header?

=====
Here's a good function header?
assistant
#Here's a good function header.

def _ParameterDecorator(naming_type, testcases):