title: how should I convert string to integer and sum the list?
body: <p>I want to sum up the list of string. I tried to convert strings to integers by using for loop and int(). But it didn't work. What should I do? Thank you for your answer!</p>
  
  <pre><code>a = ['1','2','3']
  total = 0
  for i in a:
      int(i)
      total = total + i
  
  print(total) #expected output:6
  </code></pre>