def follow_link(key, options = {})
      if link = links[key = key.to_s]
        response = API.send link[:method], link[:href], options[:body], options
        if resource_class = link[:resource_class]
          response = resource_class.from_response response
          response.attributes[self.class.member_name] = self
        end
        response
      end
    rescue Recurly::API::NotFound
      raise unless resource_class
    end
def follow_link(key, options = {})
      if link = links[key = key.to_s]
        response = API.send link[:method], link[:href], options[:body], options
        if resource_class = link[:resource_class]
          response = resource_class.from_response response
          response.attributes[self.class.member_name] = self
        end
        response
      end
    rescue Recurly::API::NotFound
      raise unless resource_class
    end
Fetch the value of a link by following the associated href.

 @param key [Symbol, String] The name of the link to be followed.
 @param options [Hash] A hash of API options.
 @example
   account.read_link :billing_info # => <Recurly::BillingInfo>