title: Multiply every element of a list by a number
body: <p>I would like to multiply all elements of a list by a number. I know the other ways to do it but I want to know Why isn't this working? I am getting the very same list as an output.</p>
  
  <pre><code>lst = eval(input('enter a list'))
  for num in lst:
       num = num * 2
  print(lst)
  </code></pre>