def read_info_file(data_dir, info_file):
labels = []<EOL>with open(os.path.join(data_dir, info_file), '<STR_LIT:r>') as f:<EOL><INDENT>labels = [int(line.split()[<NUM_LIT:0>]) for line in f]<EOL><DEDENT>return torch.LongTensor(labels)<EOL>
Return a Tensor containing the list of labels
       Read the file and keep only the ID of the 3D point.