def get_activities(self):
<EOL>collection = JSONClientValidated('<STR_LIT>',<EOL>collection='<STR_LIT>',<EOL>runtime=self._runtime)<EOL>result = collection.find(self._view_filter()).sort('<STR_LIT>', DESCENDING)<EOL>return objects.ActivityList(result, runtime=self._runtime, proxy=self._proxy)<EOL>
Gets all ``Activities``.

        In plenary mode, the returned list contains all known activites
        or an error results. Otherwise, the returned list may contain
        only those activities that are accessible through this session.

        return: (osid.learning.ActivityList) - a ``ActivityList``
        raise:  OperationFailed - unable to complete request
        raise:  PermissionDenied - authorization failure
        *compliance: mandatory -- This method must be implemented.*