How to use the pyactiveresource.activeresource.formats.JSONFormat function in pyactiveresource

version = property(get_version, set_version, None,
                      'Shopify Api Version')

    def get_url(cls):
        return getattr(cls._threadlocal, 'url', ShopifyResource._url)

    def set_url(cls, value):
        ShopifyResource._url = cls._threadlocal.url = value

    url = property(get_url, set_url, None,
                      'Base URL including protocol and shopify domain')


@six.add_metaclass(ShopifyResourceMeta)
class ShopifyResource(ActiveResource, mixins.Countable):
    _format = formats.JSONFormat
    _threadlocal = threading.local()
    _headers = {'User-Agent': 'ShopifyPythonAPI/%s Python/%s' % (shopify.VERSION, sys.version.split(' ', 1)[0])}
    _version = None
    _url = None

    def __init__(self, attributes=None, prefix_options=None):
        if attributes is not None and prefix_options is None:
            prefix_options, attributes = self.__class__._split_options(attributes)
        return super(ShopifyResource, self).__init__(attributes, prefix_options)

    def is_new(self):
        return not self.id

    def _load_attributes_from_response(self, response):
        if response.body.strip():
            self._update(self.__class__.format.decode(response.body))

def __init__(self, site, user=None, password=None, timeout=None,
                 format=formats.JSONFormat):
        super(ShopifyConnection, self).__init__(site, user, password, timeout, format)