Failure in prepare command while filtering by --vpc-ids

I have completed the collect and a normal prepare works fine but in order to make the output more workable i have been trying to filter by the --vpc-ids. I have gotten it to work by specifying --regions & --vpc-ids but mainly i get the error below. I have checked the collect files under account data and it has the information about the vpc id in question. The filter for vpc names fails also.

`Traceback (most recent call last):
File "cloudmapper.py", line 72, in
main()
File "cloudmapper.py", line 66, in main
commands[command].run(arguments)
File "/home/cloudmapper/commands/prepare.py", line 819, in run
prepare(account, config, outputfilter)
File "/home/cloudmapper/commands/prepare.py", line 660, in prepare
cytoscape_json = build_data_structure(account, config, outputfilter)
File "/home/cloudmapper/commands/prepare.py", line 477, in build_data_structure
add_node_to_subnets(region, node, nodes)
File "/home/cloudmapper/commands/prepare.py", line 329, in add_node_to_subnets
if len(node.subnets) == 0 and vpc.local_id == node._parent.local_id:`