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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_asset_to_repository(self, asset_id, repository_id):
 """Adds an existing ``Asset`` to a ``Repository``. arg: asset_id (osid.id.Id):
 the ``Id`` of the ``Asset`` arg: repository_id (osid.id.Id):
 the ``Id`` of the ``Repository`` raise: AlreadyExists - ``asset_id`` already assigned to ``repository_id`` raise: NotFound - ``asset_id`` or ``repository_id`` not found raise: NullArgument - ``asset_id`` or ``repository_id`` is ``null`` raise: OperationFailed - unable to complete request raise: PermissionDenied - authorization failure *compliance: mandatory -- This method must be implemented.* """

        # Implemented from template for
        # osid.resource.ResourceBinAssignmentSession.assign_resource_to_bin
        mgr = self._get_provider_manager('REPOSITORY', local=True)
        lookup_session = mgr.get_repository_lookup_session(proxy=self._proxy)
        lookup_session.get_repository(repository_id)  # to raise NotFound
        self._assign_object_to_catalog(asset_id, repository_id)