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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def assign_assessment_part_to_bank(self, assessment_part_id, bank_id):
 """Adds an existing ``AssessmentPart`` to an ``Bank``. arg: assessment_part_id (osid.id.Id):
 the ``Id`` of the ``AssessmentPart`` arg: bank_id (osid.id.Id):
 the ``Id`` of the ``Bank`` raise: AlreadyExists - ``assessment_part_id`` is already assigned to ``bank_id`` raise: NotFound - ``assessment_part_id`` or ``bank_id`` not found raise: NullArgument - ``assessment_part_id`` or ``bank_id`` is ``null`` raise: OperationFailed - unable to complete request raise: PermissionDenied - authorization failure *compliance: mandatory -- This method must be implemented.* """

        mgr = self._get_provider_manager('ASSESSMENT', local=True)
        lookup_session = mgr.get_bank_lookup_session(proxy=self._proxy)
        lookup_session.get_bank(bank_id)  # to raise NotFound
        self._assign_object_to_catalog(assessment_part_id, bank_id)