divide a list into three separate list

def divide(list):
  list_one = list[:len(list)/3]
  list_two = list[len(list)/3+1:2*(len(list)/3)]
  list_three = list[2*(len(list)/3)+1:]
  return list_one, list_two, list_three
  
  
list_one, list_two, list_three = divide(list)