code: func (sl *SkipList) Delete(comparators ...common.Comparator) common.Comparators {
  	deleted := make(common.Comparators, 0, len(comparators))
  
  	for _, cmp := range comparators {
  		deleted = append(deleted, sl.delete(cmp))
  	}
  
  	return deleted
  }
docs: // Delete will remove the provided keys from the skiplist and return
  // a list of in-order Comparators that were deleted.  This is a no-op if
  // an associated key could not be found.  This is an O(log n) operation.