title: Assigning a function to a variable
body: <p>Let's say I have a function </p>
  
  <pre><code>def x():
      print(20)
  </code></pre>
  
  <p>Now I want to assign the function to a variable called <code>y</code>, so that if I use the <code>y</code> it calls the function <code>x</code> again. if i simply do the assignment <code>y = x()</code>, it returns <code>None</code>.</p>