new_contents: import csv
  
  def test():
      with open("CVfolds_2.txt", newline='') as id2set, open("rec_id2filename.txt", newline='') as id2file, open("rec_labels_test_hidden.txt", newline='') as id2label:
          with open("file2label.csv", 'w', newline='') as file2label:
              readId2Label = csv.reader(id2label)
              readId2Set = csv.reader(id2set)
              readId2File = csv.reader(id2file)
              file2labelwriter = csv.writer(file2label)
  
              id2file = {}
              for r in readId2File:
                  if r[0] == 'rec_id':
                      print("Reading id to file...")
                  else:
                      id2file[r[0]] = r[1]
  
              print("Done reading id to file.")
  
              nb_samples = 0
              nb_bird_present = 0
  
              print("Creating file to labels csv...")
              for (id2label, id2set) in zip(readId2Label, readId2Set):
                  if(id2set[0] != id2label[0]):
                      raise ValueError
                  iden = id2set[0]
                  if(id2set[1] == '0'):
                      nb_samples += 1
                      if(len(id2label) > 1):
                          labels = id2label[1:]
                          nb_bird_present += 1
                          f = id2file[iden]
                          file2labelwriter.writerow([f] + labels)
                      else:
                          file2labelwriter.writerow([f])
  
              print("Number of training samples: ", nb_samples)
              print("Number of training samples with birds present: ", nb_bird_present)
  
subject: Add a script which structures the mlsp2013 data