def call(req, args={}, &block)
      oauth_args = args.delete(:oauth) || {}
      http_response = @oauth_consumer.post_form(REST_PATH, @access_secret, {:oauth_token => @access_token}.merge(oauth_args), build_args(args, req))
      process_response(req, http_response.body)
    end
def call(req, args={}, &block)
      oauth_args = args.delete(:oauth) || {}
      http_response = @oauth_consumer.post_form(REST_PATH, @access_secret, {:oauth_token => @access_token}.merge(oauth_args), build_args(args, req))
      process_response(req, http_response.body)
    end
This is the central method. It does the actual request to the flickr server.

 Raises FailedResponse if the response status is _failed_.