code: func (b TestToBuildData) GetDataPerBuild(job, build, test, node string) *DataPerBuild {
  	if _, ok := b[test]; !ok {
  		b[test] = &DataPerTest{
  			Job:  job,
  			Data: map[string]DataPerNode{},
  		}
  	}
  	if _, ok := b[test].Data[node]; !ok {
  		b[test].Data[node] = DataPerNode{}
  	}
  	if _, ok := b[test].Data[node][build]; !ok {
  		b[test].Data[node][build] = &DataPerBuild{}
  	}
  	return b[test].Data[node][build]
  }
docs: // GetDataPerBuild creates a DataPerBuild structure for the given build using
  // the specified job, test, and node if it does not exist, and then returns it.