new_contents: #!/usr/bin/python
  #coding:utf-8
  
  # 元组 其内容是不可变的
  
  u = 1,2,3; # 定义
  print u;
  print len(u);
  b = 1, 3, (3, 5); # 可嵌套
  print b;
  
  # 元组的封装的逆操作
  a = 3;
  b = 4;
  a, b = (b,a);
  print a, b;
  
  def triple(x, y, z):
      return (3 * x, 3 * y, 3 * z);
  
  a, b, c = triple(1, 2, 3);
  print a, b, c; #3, 6, 9
subject: add tuple