Get a formatted JSON representation of an item's data hosted in ArcGIS Online

item_details.py

import json
import tortilla

class AGOL:
    """ A class for administering an ArcGIS Online account"""

    def __init__(self, in_username, in_password, expiration=60):
        self.agol = tortilla.wrap('https://www.arcgis.com')
        self.username = in_username
        self.password = in_password
        self.expiration = expiration
        self.token = self.gen_token()

    def gen_token(self):
        """ Returns a token given a username and password """

        param = dict(username=self.username, password=self.password, expiration=self.expiration, client='referer',
                     referer='https://www.arcgis.com', f='json')

        token = self.agol.sharing.rest.generateToken.post(params=param)

        if hasattr(token, 'error'):
            print token.error.message
            print token.error.details
        else:
            return token    

    def item_data(self, item_id):
        """ Returns the data for a given AGOL item """

        param = dict(token=self.token.token, f='json')

        data = self.agol.sharing.rest.content.items(item_id).data.get(params=param)

        if hasattr(data, 'error'):
            print data.error.message
            print data.error.details
        else:
            return data

if __name__ == "__main__":
    
    username = 'username'
    password = 'password'

    agol = AGOL(username, password)

    print "\nITEM DATA"
    print "========="
    
    item = raw_input('Item id: ')
    data = agol.item_data(item)
    
    print json.dumps(obj=data, indent=4)    

    print "\nfinished"

Requires the tortilla package
pip install tortilla