如何在python中查找list的重复元素dict？

def find_duplicates(lst):
    count_dict = {}
    duplicates = []
    for item in lst:
        if item in count_dict:
            count_dict[item] += 1
            if count_dict[item] == 2:
                duplicates.append(item)
        else:
            count_dict[item] = 1
    return duplicates

# 示例用法
my_list = [1, 2, 3, 4, 2, 3, 5, 6, 1]
result = find_duplicates(my_list)
print(result)  # 输出: [2, 3, 1]

def find_duplicates(lst):
    return list(set([x for x in lst if lst.count(x) > 1]))

# 示例用法
my_list = [1, 2, 3, 4, 2, 3, 5, 6, 1]
result = find_duplicates(my_list)
print(result)  # 输出: [1, 2, 3]