title: Implement packing/unpacking in an object
body: <p>I have a class that only contains attributes and I would like packing/unpacking to work on it. What <code>collections.abc</code> should I implement to get this behaviour?</p>
  
  <pre><code>class Item(object):
  
      def __init__(self, name, age, gender)
          self.name = name
          self.age = age
          self.gender = gender
  
  a, b, c = Item("Henry", 90, "male")
  </code></pre>
  
  <p>I would like to avoid using a <code>namedtuple</code>.</p>