def find(self, k):
        'Return first item with a key == k.  Raise ValueError if not found.'
        i = bisect_left(self._keys, k)
        if i != len(self) and self._keys[i] == k:
            return self._items[i]
        raise ValueError('No item found with key equal to: %r' % (k,))
Return first item with a key == k.  Raise ValueError if not found.
recipes/Python/577197_SortedCollection/recipe-577197.py