python - 按列对 csv 文件进行排序

Question

我想根据第一列的内容按字母顺序对csv文件中的数据进行排序。例如，如果文件包含:

city/month,Jan,Feb,Mar,Apr

Melbourne,41.2,35.5,37.4,29.3

Brisbane,31.3,40.2,37.9,29

Darwin,34,34,33.2,34.5

它将被排序为:

city/month,Jan,Feb,Mar,Apr

Brisbane,31.3,40.2,37.9,29

Darwin,34,34,33.2,34.5

Melbourne,41.2,35.5,37.4,29.3

到目前为止，我所做的是正确排序，但它没有正确返回答案，它不是以表格格式返回答案，而是以列表形式返回所有内容 - 知道为什么会这样吗？

import csv
import operator

def sort_records(csv_filename, new_filename):

  f = open(csv_filename)

  csv1 = csv.reader(f, delimiter = ',')

  new_filename = sorted(csv1)

  return new_filename

  f.close()

Answer 1

>>> import csv
>>> import operator

>>> def sort_records(csv_filename, new_filename):
...     with open(csv_filename, 'r') as i, open(new_filename, 'w') as o:
...         reader = csv.reader(i, delimiter = ',')
...         writer = csv.writer(o, delimiter=',')
...         writer.writerow(next(reader)) # header row
...         writer.writerows(sorted(reader, key=operator.itemgetter(0)))

>>> sort_records('a.csv', 'b.csv')