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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 unassign_assessment_from_bank(self, assessment_id, bank_id):
 """Removes an ``Assessment`` from a ``Bank``. arg: assessment_id (osid.id.Id):
 the ``Id`` of the ``Assessment`` arg: bank_id (osid.id.Id):
 the ``Id`` of the ``Bank`` raise: NotFound - ``assessment_id`` or ``bank_id`` not found or ``assessment_id`` not assigned to ``bank_id`` raise: NullArgument - ``assessment_id`` or ``bank_id`` is ``null`` raise: OperationFailed - unable to complete request raise: PermissionDenied - authorization failure occurred *compliance: mandatory -- This method must be implemented.* """

        # Implemented from template for
        # osid.resource.ResourceBinAssignmentSession.unassign_resource_from_bin
        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._unassign_object_from_catalog(assessment_id, bank_id)