code: func (sba *sparseBitArray) GetBit(k uint64) (bool, error) {
  	index, position := getIndexAndRemainder(k)
  	i := sba.indices.get(index)
  	if i == -1 {
  		return false, nil
  	}
  
  	return sba.blocks[i].get(position), nil
  }
docs: // GetBit gets the bit at the given position.