input: Write a Python function that computes the highest total value from a list of tuples.
  assert highest_total([('Juan Whelan', 90),('Sabah Colley', 88),('Peter Nichols', 7),('Juan Whelan', 122),('Sabah Colley', 84)]) == ('Juan Whelan', 212)
  assert highest_total([('Juan Whelan', 50),('Sabah Colley', 48),('Peter Nichols', 37),('Juan Whelan', 22),('Sabah Colley', 14)]) == ('Juan Whelan', 72)
  assert highest_total([('Juan Whelan', 10),('Sabah Colley', 20),('Peter Nichols', 30),('Juan Whelan', 40),('Sabah Colley', 50)]) == ('Sabah Colley', 70)
output: def highest_total(records):
      totals = {}
      for name, value in records:
          if name in totals:
              totals[name] += value
          else:
              totals[name] = value
      return max(totals.items(), key=lambda x: x[1])