1import os 2 3 4def application(env, start_response): 5 variables = env.get('HTTP_X_VARIABLES').split(',') 6 7 body = ','.join( 8 [str(os.environ[var]) for var in variables if var in os.environ] 9 ) 10 body = body.encode() 11 12 start_response('200', [('Content-Length', str(len(body)))]) 13 return body 14