python文件对重复元素打印

Question

1.dupgbk.txt文件中，要统计该列表中包含的“相邻的相同元素” 的值，并将该值打印到屏幕。
(文件内容如下：
1
1
a
ssq
o
o
o
4
44
78
[1, 2]
[1, 2]
33
open
1
1
1
1
o
o

Answer 1

这个意思？
filename1 = dirname + '\\dupgbk.txt'
with open(filename1, 'r', encoding='utf-8') as f:
    c = f.read().split("\n")
    i = 0
    j = 1
    while i + j <= len(c):
        j = 1
        while i + j < len(c):
            if c[i+j] ==c[i]:
                j +=1
            else:
                break
        if j != 2:
            i += j
        else:
            print(c[i])
            i = i + j            

    if i == len(c) - 2 and c[i] == c[i+1]:
        print(c[i])
'''--result
1
[1, 2]
o
'''