内置函数3--zip

• # zip
  # l1=[1,2,3]
  # s='hel'
  # for i in zip(l1,s):
  #     print(i)#(1, 'h')(2, 'e')(3, 'l')

•   应用实例

• row = models.Teacher.objects.filter(id=nid).first()
  class_ids = row.c2t.values_list('id')
  print('--??',row,class_ids)
  print("--?1",zip(*class_ids),list(zip(*class_ids)))
  id_list = list(zip(*class_ids))[0] if list(zip(*class_ids)) else []

• 
  
  # salaries={
  #     'egon':3000,
  #     'alex':10000,
  #     'wupeiq':1000,
  #     'yuanhao':250
  # }
  # z=zip(salaries.values(),salaries.keys())#
  # print(max(z))#(10000, 'alex')#
  # print(max('2a1','3a2'))#3a2大
  
  # sorted
  # l=[2,1,3,4,22,44]
  # print(sorted(l))#返回值是列表，默认是升序，

• 排序后，是重新开辟一块内存，所以要重新赋值给变量，值才会变

•     ==列表去重与排序==

• l = [1,12,2,3,22,13,44,2,3]
  print(sorted(set(l),key=l.index))

• 即s=sorted(l),print(s)
  # print(sorted(l,reverse=True))#降序排列
  # s='hello abc'
  # print(sorted(s))
  
  salaries={
      'egon':3000,
      'alex':10000,
      'wupeiq':1000,
      'yuanhao':250
  }
  # print(sorted(salaries))#默认是按照字典salaries的key去排序的
  # print(sorted(salaries,key=lambda x:salaries[x]))
  print(sorted(salaries,key=lambda x:salaries[x],reverse=True))

• print(sorted(salaries.items(),key=lambda x:x[1]))