code: func FMSketchFromProto(protoSketch *tipb.FMSketch) *FMSketch {
  	sketch := &FMSketch{
  		hashset: make(map[uint64]bool),
  		mask:    protoSketch.Mask,
  	}
  	for _, val := range protoSketch.Hashset {
  		sketch.hashset[val] = true
  	}
  	return sketch
  }
docs: // FMSketchFromProto converts FMSketch from its protobuf representation.