def index(self, item):
        'Find the position of an item.  Raise ValueError if not found.'
        k = self._key(item)
        i = bisect_left(self._keys, k)
        j = bisect_right(self._keys, k)
        return self._items[i:j].index(item) + i
def index ( self , item ) : k = self . _key ( item ) i = bisect_left ( self . _keys , k ) j = bisect_right ( self . _keys , k ) return self . _items [ i : j ] . index ( item ) + i
Find the position of an item.  Raise ValueError if not found.