title: Why do you need to assign class to variable to use it? Unlike function
body: <p>I am just learning, and have a confusion
  In this code I assign  dice=Dice().. Why not just use Dice.roll()?? It yells at me about positional arguments ;(
  Could you please clarify a difference, why do I need that in comparison to functions?</p>
  <pre><code>import random
  class Dice:
      def roll(self):
          a=random.randint(1,6)
          b = random.randint(1, 6)
          return a,b
  
  
  dice=Dice()
  print(dice.roll())
  </code></pre>