paring.py

#!/usr/bin/env python3
# coding: utf-8
# (File name: paring.py)
# Author: SENOO, Ken
# License: CC0
# (Last update: 2015-07-26T20:32+09:00)

import itertools

FR = "./項目リスト.txt"
with open(FR, "U", encoding="utf-8") as fr:
    item = fr.read().split()
"""
洪水警戒体制  洪水調節  計画高降水量70%（50%）  非常用洪水吐放流  （解除）非常用洪水吐放流  （解除）計画高降水量70%（50%）  （解除）洪水調節  （解除）洪水警戒体制
"""

FW = "./out.csv"
with open(FW, "w", encoding="utf-8-sig", newline="\n") as fw:
    for left, right in itertools.combinations_with_replacement(item, 2):
        fw.write(left+"→"+right+"\n")
    for left, right in itertools.combinations(item[::-1], 2):
        fw.write(left+"→"+right+"\n")