human
Complete the below
def crossdomain(origin=None, methods=None, headers=None, max_age=21600, attach_to_all=True, automatic_options=True):

    ''''Decorator to set crossdomain configuration on a Flask view
    For more details about it refer to:
    http://flask.pocoo.org/snippets/56/'
    '''
assistant
#Here is the Python program you requested.
    if (methods is not None):
        methods = ',    '.join(sorted((x.upper() for x in methods)))
    if ((headers is not None) and (not isinstance(headers, string_types))):
        headers = ',    '.join((x.upper() for x in headers))
    if (not isinstance(origin, string_types)):
        origin = ',    '.join(origin)
    if isinstance(max_age, timedelta):
        max_age = max_age.total_seconds()
    def get_methods():
        options_resp = current_app.make_default_options_response()
        return options_resp.headers['allow']
    def decorator(f):
        @wraps(f)
        def wrapped_function(*args, **kwargs):
            if (automatic_options and (request.method == 'OPTIONS')):
                resp = current_app.make_default_options_response()
            else:
                resp = make_response(f(*args, **kwargs))
            if ((not attach_to_all) and (request.method != 'OPTIONS')):
                return resp
            h = resp.headers
            h['Access-Control-Allow-Origin'] = origin
            h['Access-Control-Allow-Methods'] = get_methods()
            h['Access-Control-Max-Age'] = str(max_age)
            requested_headers = request.headers.get('Access-Control-Request-Headers')
            if (headers is not None):
                h['Access-Control-Allow-Headers'] = headers
            elif requested_headers:
                h['Access-Control-Allow-Headers'] = requested_headers
            return resp
        f.provide_automatic_options = False
        return update_wrapper(wrapped_function, f)
    return decorator