Parsing JSON array into class instance objects?

json, python

Solution

If you always get the same keys, you can use `**` to easily construct your instances. Making the `Metro` a `namedtuple` will simplify your life if you are using it simply to hold values:

from collections import namedtuple
Metro = namedtuple('Metro', 'code, name, country, continent, timezone, coordinates,
                   population, region')

then simply

import json
data = json.loads('''...''')
metros = [Metro(**k) for k in data["metros"]]

Problem

I'm trying to parse some data in Python I have some JSON: ``` { "data sources": [ "http://www.gcmap.com/" ], "metros": [ { "code": "SCL", "continent": "South America", "coordinates": { "S": 33, "W": 71 }, "country": "CL", "name": "Santiago", "population": 6000000, "region": 1, "timezone": -4 }, { "code": "LIM", "continent": "South America", "coordinates": { "S": 12, "W": 77 }, "country": "PE", "name": "Lima", "population": 9050000, "region": 1, "timezone": -5 } ] } ``` If I wanted to parse the `"metros"` array into and array of Python class `Metro` objects, how would I setup the class? I was thinking: ``` class Metro(object): def __init__(self): self.code = 0 self.name = "" self.country = "" self.continent = "" self.timezone = "" self.coordinates = [] self.population = 0 self.region = "" ``` So I want to go through each metro and put the data into a corresponding `Metro` object and place that object into a Python array of objects...How can I loop through the JSON metros?

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