Python入門
CSV読み書き（csvモジュール）

from pprint import pprint
import csv
with open("./test/file01.txt", "r", encoding="shift-jis") as f:
    reader = csv.reader(f, dialect='excel-tab')
    row = [r for r in reader]
pprint(row, width=20)

import csv
csv.register_dialect("colon", delimiter=':')
with open('./test.csv', 'r', encoding="utf-8") as f:
    reader = csv.reader(f, dialect='colon')
    [print(r) for r in reader]

from pprint import pprint
import csv
with open("./test/file01.csv", "r", encoding="utf-8") as f:
    reader = csv.reader(f)
    row = [r for r in reader]
pprint(row, width=20)

from pprint import pprint
import csv
with open("./test/file01.csv", "r", encoding="utf-8") as f:
    reader = csv.DictReader(f)
    row = [r for r in reader]
pprint(row, width=50)

from pprint import pprint
from pathlib import Path
import csv


p = Path("./test")
files = list(p.glob("*.csv"))


row = []
for file in files:
    with open(file, "r", encoding="utf-8") as f:
        reader = csv.reader(f)
        for r in reader:
            row.append(r)


pprint(row)

from pprint import pprint
from pathlib import Path
import csv


p = Path("./test")
files = list(p.glob("*.csv"))


row = []
for file in files:
    with open(file, "r", encoding="utf-8") as f:
        reader = csv.reader(f)
        if len(row) == 0:
            #最初のcsvの1行目を見出しで使用
            field_list = next(reader)
        else:
            #最初のcsv以外は単純スキップ
            next(reader) 
        for r in reader:
            row.append(r)


print(field_list)
pprint(row)

from pathlib import Path
import csv


p = Path("./test")
files = list(p.glob("*.csv"))


row = []
for file in files:
    with open(file, "r", encoding="utf-8") as f:
        reader = csv.reader(f)
        if len(row) == 0:
            #最初のcsvの1行目を見出しで使用
            field_list = next(reader)
        else:
            #最初のcsv以外は単純スキップ
            next(reader) 
        for r in reader:
            row.append(r)


#上の階層にfile99.csvとして出力

with open("./file99.csv", "w", encoding="shift-jis") as f:
    writer = csv.writer(f, lineterminator="\n")
    writer.writerow(field_list)
    writer.writerows(row)

from pathlib import Path
import csv


p = Path("./test")
files = list(p.glob("*.csv"))


row = []
for file in files:
    with open(file, "r", encoding="utf-8") as f:
        reader = csv.DictReader(f)
        if len(row) == 0:
            #最初のcsvの1行目を見出しで使用
            field_list = reader.fieldnames
        for r in reader:
            row.append(r)


#上の階層にfile99.csvとして出力
with open("./file99.csv", "w", encoding="shift-jis") as f:
    writer = csv.DictWriter(f, fieldnames=field_list, lineterminator="\n")
    writer.writeheader() #列名を付ける指定
    writer.writerows(row)