Is a nameop a valid state-preorder operation?

def state_create_is_valid( nameop ):
    """
    Is a nameop a valid state-preorder operation?
    """
    assert '__state_create__' in nameop, "Not tagged with @state_create"
    assert nameop['__state_create__'], "BUG: tagged False by @state_create"
    assert '__preorder__' in nameop, "No preorder"
    assert '__table__' in nameop, "No table given"
    assert '__history_id_key__' in nameop, "No history ID key given"
    assert nameop['__history_id_key__'] in nameop, "No history ID given"
    assert '__always_set__' in nameop, "No always-set fields given"

    return True