code: func (d *Dataset) LocalLimit(name string, n int, offset int) *Dataset {
  	ret, step := add1ShardTo1Step(d)
  	ret.IsLocalSorted = d.IsLocalSorted
  	ret.IsPartitionedBy = d.IsPartitionedBy
  	step.SetInstruction(name, instruction.NewLocalLimit(n, offset))
  	step.Description = fmt.Sprintf("local limit %d", n)
  	return ret
  }
docs: // LocalLimit take the local first n rows and skip all other rows.