如何按行獲取列表中str項目的所有組合python

Question

我有一個fasta文件如下：

>seq1
AAAAAAAA
>seq2
TTTTTTTT
>seq3
CCCCCCCC
>seq4
GGGGGGGG

我想獲得所有行的組合(except the ones that start with > sign) 。 所需的 output 應該是：

AAAAAAAA
TTTTTTTT

AAAAAAAA
CCCCCCCC

AAAAAAAA
GGGGGGGG

TTTTTTTT
CCCCCCCC

TTTTTTTT
GGGGGGGG

CCCCCCCC
GGGGGGGG

我的一段代碼在這里，但缺少組合的最后一步：

from Bio import SeqIO

list1=[]
with open('file1.fa', 'r') as file1:
    for record1 in SeqIO.parse(file1, 'fasta'):
        list1.append(record1.seq)


for i in list1:
    print(i)

謝謝

Answer 1

嘗試

from itertools import combinations as com

lst = ['A', 'B', 'C', 'D']
combi = list(com(lst, 2))

for entry in combi:
    print(entry[0])
    print(entry[1])
    print()

output

A
B

A
C

A
D

B
C

B
D

C
D