fix a syntax error

ldap.py

@@ -9,7 +9,7 @@ if 'LDAP_HOST' in config:
 		user = LDAP_USERRE.sub(r'', user.lower())
 		try:
 			conn = ldap3.Connection(ldap3.Server(config['LDAP_HOST'], port=config['LDAP_PORT'], use_ssl=True), 'fsmpi\\%s'%user, password, auto_bind=True, check_names=False)
-		except ldap3.core.exceptions.LDAPBindError, ldap3.core.exceptions.LDAPPasswordIsMandatoryError:
+		except (ldap3.core.exceptions.LDAPBindError, ldap3.core.exceptions.LDAPPasswordIsMandatoryError):
 			return {}, []
 		conn.search("cn=users,dc=fsmpi,dc=rwth-aachen,dc=de", "(cn=%s)"%user, attributes=['memberOf', 'givenName', 'sn'])
 		info = {'uid': user, 'givenName': conn.response[0]['attributes']['givenName'][0], 'sn': conn.response[0]['attributes']['sn'][0]}