log-analytics problem with w3c extended format (no replies)

using the w3c extended format crashes for me when I added a custom column

My Command is as follows....

/home/weblogic/Python-2.7.8/python /home/weblogic/piwik-log-analytics/import_logs.py --url=http://su-soametricsprd01/piwik --idsite=1 --token-auth=8b4da1b22b12c2be757a0cf6db2811f3 --log-format-name=w3c_extended --w3c-map-field=cs\(X-Forwarded-For\)=c-ip /u01/app/oracle/product/ofusion/user_projects/domains/websrv/servers/logs/access.log

I've lost the error message, but is was at line 777 'if default_name not in type(format).fields:"

I changed the line to be " if default_name not in W3cExtendedFormat.fields: " Which fixed the issue.

Here's a snippet of my log file

#Version:	1.0
#Fields:	date time cs-uri-stem cs-uri-query cs(X-Forwarded-For) cs(User-Agent) cs(Referer) sc-status sc-bytes cs-host cs-username time-taken
#Software:	WebLogic
#Start-Date:	2015-07-14	16:50:45
2015-07-14	16:50:45	/sale-history-service-2.0-GA/saleHistoryService/	-	"10.1.44.70"	"Apache-HttpClient/4.1.1 (java 1.5)"	-	200	-	-	-	0.716
2015-07-14	16:50:45	/sale-history-service-2.0-GA/saleHistoryService/	-	"10.1.44.70"	"Apache-HttpClient/4.1.1 (java 1.5)"	-	200	-	-	-	0.723

Am I doing something wrong ?