title: how to return length of a list from a class in python
body: <p>So I get this error when I try to get the len() of my list from my class:
  TypeError: object of type 'Stuff' has no len()
  when I try:</p>
  
  <pre><code>&gt;&gt;&gt; s = Stuff()
  &gt;&gt;&gt; len(s)
  error instead of showing 0 like:
  &gt;&gt;&gt; l = []
  &gt;&gt;&gt; len(l)
  0
  </code></pre>
  
  <p>Code:</p>
  
  <pre><code>class Stuff():
      def __init__(self):
          self.lst = []
  </code></pre>