Yes, it's a dict. Here is usage: https://github.com/softlayer/softlayer-api-python-client/blob/master/SoftLayer/CLI/modules/ssl.py#L66

This is the call that it feeds into: http://sldn.softlayer.com/reference/services/SoftLayer_Security_Certificate/createObject
This is the 'object' (which in python maps to dicts): http://sldn.softlayer.com/reference/datatypes/SoftLayer_Security_Certificate