ttempts to build and insert an element into the        *  %unordered_set.        *  @param __args  Arguments used to generate an element.        *  @return  A pair, of which the first element is an iterator that points        *           to the possibly inserted element, and the second is a bool        *           that is true if the element was actually inserted.        *        *  This function attempts to build and insert an element into the        *  %unordered_set. An %unordered_set relies on unique keys and thus an 