title: TypeError: __str__ returned non-string (type tuple)
body: <pre><code>def __str__(self):
      summa = 0
      for a in self.__pisteet:
          summa += a
          mjono += str(a)
      return "{:s} {:s} yhteensa", summa, "pistetta".format(self.__nimi, mjono)  
  </code></pre>
  
  <p>So there are multiple players and I should be able to print all their names, all scores and the sum of scores.</p>
  
  <pre><code>TypeError: __str__ returned non-string (type tuple)
  </code></pre>