code: def find_le_index(self, k):
          'Return last item with a key <= k.  Raise ValueError if not found.'
          i = bisect_right(self._keys, k)
          if i:
              return i - 1
          raise ValueError('No item found with key at or below: %r' % (k,)f find_le_index(self, k):
          'Return last item with a key <= k.  Raise ValueError if not found.'
          i = bisect_right(self._keys, k)
          if i:
              return i - 1
          raise ValueError('No item found with key at or below: %r' % (k,))
docs: Return last item with a key <= k.  Raise ValueError if not found.