<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def isAllowed(self, assoc_type, session_type):
 """Is this combination of association type and session type allowed?"""

        assoc_good = (assoc_type, session_type) in self.allowed_types
        matches = session_type in getSessionTypes(assoc_type)
        return assoc_good and matches