func_code: def maximum(l):
      A = 'null'
      highest = A
      for c in l:
          if maximum == A:
              maximum = c
          elif c > maximum:
              maximum = c
      return maximum
annotation: def maximum(l):
      A = 'null'
      highest = A
      for c in l:
          if highest == A:
              highest = c
          elif c > highest:
              highest = c
      return highest
  