Help with JSON

    def balance_io(cls, address):
        h = urllib2.urlopen('http://btc.blockr.io/api/v1/address/info/%s' % address)
        json = simplejson.load(h)
        json = simplejson.load(json)
        f = data['balance']
        return f

This is what the page returns, I am just trying to get the balance:

{
	"status": "success",
	"data": {
		"address": "14xg41kHFVfLX5LjYD4QbWaVwTNUiWK14n",
		"is_unknown": false,
		"balance": 0,
		"totalreceived": 0.26362206,
		"nb_txs": 4,
		"first_tx": {
			"time_utc": "2014-03-31T18:18:07Z",
			"tx": "46e99e14a6a413713565f8a20b83d05670ad99f76948f7e142a3ae3a11785254",
			"block_nb": "293433",
			"value": 0.1300608,
			"confirmations": 1407
		},
		"last_tx": {
			"time_utc": "2014-04-05T18:02:09Z",
			"tx": "de3547d3b59f1b0104d37dd833706aefaeae4444c727216bf9a64fd899d50dfd",
			"block_nb": "294382",
			"value": -0.13356126,
			"confirmations": 458
		},
		"is_valid": true
	},
	"code": 200,
	"message": ""
}