human
I wrote the below code

    def check_single_kv_pair(kv, key):
        kv.push(key, mx.nd.ones(shape))
        val = mx.nd.empty(shape)
        kv.pull(key, out=val)
        check_diff_to_scalar(val, 1)
    check_single_kv_pair(init_kv(), 3)
    check_single_kv_pair(init_kv_with_str(), 'a')

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

def test_single_kv_pair():