input: Write a python function to find the highest total from a list of name-score pairs. 
  assert max_total_score([('Juan Whelan',90),('Sabah Colley',88),('Peter Nichols',7),('Juan Whelan',122),('Sabah Colley',84)])==('Juan Whelan', 212)
  assert max_total_score([('Juan Whelan',50),('Sabah Colley',48),('Peter Nichols',37),('Juan Whelan',22),('Sabah Colley',14)])==('Juan Whelan', 72)
  assert max_total_score([('Juan Whelan',10),('Sabah Colley',20),('Peter Nichols',30),('Juan Whelan',40),('Sabah Colley',50)])==('Sabah Colley', 70)
output: def max_total_score(pairs):
      scores = {}
      for name, score in pairs:
          if name in scores:
              scores[name] += score
          else:
              scores[name] = score
      return max(scores.items(), key=lambda x: x[1])