You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: parallel.m
    path of file: ./repos/MataveControl/matave/+mc
    
    the code of the file until where you have to start completion: % Generates the new transfer function or new state space model of parallel connection
% Input: G, sys
% Exampl
    
function or new state space model of parallel connection
% Input: G, sys
% Example 1: G = mc.parallel(G1, G2)
% Example 2: sys = mc.parallel(sys1, sys2)
% Author: Daniel MÃ¥rtensson 2017 Oktober

function [model] = parallel(varargin)
  % Check if there is any input
  if(isempty(varargin))
    error ('Missing input')
  end