Are you ever connecting to your server and accessing the domain runtime? You should be doing something like the following:
connect("weblogic", "weblogic", "t3://localhost:7001")
domainRuntime()
# obtain session management mbean to create a session.
# This mbean instance can be used more than once to
# create/discard/commit many sessions
sessionMBean = findService(SessionManagementMBean.NAME,SessionManagementMBean.TYPE)
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