code: def sdiv(a, b):
      
      if len(a) != len(b):
          raise ValueError('Argument a and b does not have the same length')
      idx = 0
      ret = matrix(0, (len(a), 1), 'd')
      for m, n in zip(a, b):
          try:
              ret[idx] = m / n
          except ZeroDivisionError:
              ret[idx] = 1
          finally:
              idx += 1
      return ret
docs: Safe division: if a == b == 0, sdiv(a, b) == 1