Read a json file written with specific format, convert the data to 2nd dim list and write it as a csv file.

conv_json_to_csv.py

#coding:utf-8
'''
Created on 2014/7/20

@author: Tae Matsumoto
JSONファイルを読み込み、同名のCSVファイルを出力します。
読み込む対象のJSONファイルの構造は下記の通り。
[{'key':区名1, 'stat':{0:0歳人口,1:1歳人口,...}},{'key':区名2, 'stat':{0:0歳人口,1:1歳人口,...}},...]
'''

import csv, json

filename = 'yokohama_stat'

# read json file.
json_data = open(filename+'.json')
data = json.load(json_data)
json_data.close()

res = list()

# add header
tmp = list(data[0]['stat'].items()) + [('key', data[0]['key'])]
tmp.sort()
header = [x[0] for x in tmp]
res.append(header)

# add elements
for row in data:
    row_list = list(row['stat'].items()) + [('key', row['key'])]
    row_list.sort()
    vals = [x[1] for x in row_list]
    res.append(vals)

# display resulsts
print res

# write a file as csv
with open(filename+'.csv', 'wb') as f:
    mywriter = csv.writer(f, delimiter = ',')
    mywriter.writerows(res)
    f.close()