如何从列表中提取所有重复值？

Question

我有以下列表：friends = ["Brian","John","Brian", "Alena", "Brian"]。如果我使用duplicated()，我只会得到 Brian 一次，但结果应该是Brian, Brian, Brian（因为该列表包含该名称的次数是3次）。

Answer 1

尝试一下：

dups = [f for f in friends if friends.count(f) > 1]

Answer 2

 # you can try this     
  from collections import Counter
  count =  [count for item, count in Counter(friends).items() if count > 1] # this will 
   give you the count of the duplicated item
  item   =  [item for item, count in Counter(friends).items() if count > 1] # this will 
  return the item itself