code: func (c *MockClient) DeleteMulti(keys []string) []MutateResponse {
  	res := make([]MutateResponse, len(keys))
  	for i, key := range keys {
  		res[i] = c.Delete(key)
  	}
  	return res
  }
docs: // Batch version of the Delete method.  Note that the response entries
  // ordering is undefined (i.e., may not match the input ordering)