import urllib2 import traceback dbName = "swissprot" id = "HBA_HUMAN" format = "uniprot" urlBase = "http://www.ebi.ac.uk/Tools/dbfetch/dbfetch/" urlFinal = urlBase + dbName + "/" + id + "/" + format print "URL is: " + urlFinal try: response = urllib2.urlopen(urlFinal).read() print "Received " + str((len(response.splitlines()))) + " lines" print response except Exception as err: traceback.print_tb(err.__traceback__)