human
I wrote the below code

    if isinstance(__funcname, str):
        def get_funcname(_):
            return __funcname
    else:
        get_funcname = __funcname
    def _expect_dimension(expected_ndim):
        def _check(func, argname, argvalue):
            actual_ndim = argvalue.ndim
            if (actual_ndim != expected_ndim):
                if (actual_ndim == 0):
                    actual_repr = 'scalar'
                else:
                    actual_repr = ('%d-D    array' % actual_ndim)
                raise ValueError('{func}()    expected    a    {expected:d}-D    array    for    argument    {argname!r},    but    got    a    {actual}    instead.'.format(func=get_funcname(func), expected=expected_ndim, argname=argname, actual=actual_repr))
            return argvalue
        return _check
    return preprocess(**valmap(_expect_dimension, dimensions))

What's a good function header?

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

def expect_dimensions(__funcname=_qualified_name, **dimensions):