Get the orderbook for a particular stock.

        https://starfighter.readme.io/docs/get-orderbook-for-stock

def orderbook_for_stock(self, stock):
        """Get the orderbook for a particular stock.

        https://starfighter.readme.io/docs/get-orderbook-for-stock
        """
        url_fragment = 'venues/{venue}/stocks/{stock}'.format(
            venue=self.venue,
            stock=stock,
        )
        url = urljoin(self.base_url, url_fragment)
        return self.session.get(url).json()