code: public static Frame parseFrame(Key okey, File ...files) throws IOException {
      if (files == null || files.length == 0) {
        throw new IllegalArgumentException("List of files is empty!");
      }
      for (File f : files) {
        if (!f.exists())
          throw new FileNotFoundException("File not found " + f);
      }
      // Create output key if it is not given
      if(okey == null) okey = Key.make(files[0].getName());
      Key[] inKeys = new Key[files.length];
      for (int i=0; i<files.length; i++) inKeys[i] =  NFSFileVec.make(files[i])._key;
      return ParseDataset.parse(okey, inKeys);
    }
docs: Parse given file(s) into the form of single frame represented by the given key.
  
  @param okey  destination key for parsed frame
  @param files  files to parse
  @return a new frame