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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 get_objective_form_for_update(self, objective_id):
 """Gets the objective form for updating an existing objective. A new objective form should be requested for each update transaction. arg: objective_id (osid.id.Id):
 the ``Id`` of the ``Objective`` return: (osid.learning.ObjectiveForm) - the objective form raise: NotFound - ``objective_id`` is not found raise: NullArgument - ``objective_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.ResourceAdminSession.get_resource_form_for_update_template
        collection = JSONClientValidated('learning',
                                         collection='Objective',
                                         runtime=self._runtime)
        if not isinstance(objective_id, ABCId):
            raise errors.InvalidArgument('the argument is not a valid OSID Id')
        if (objective_id.get_identifier_namespace() != 'learning.Objective' or
                objective_id.get_authority() != self._authority):
            raise errors.InvalidArgument()
        result = collection.find_one({'_id': ObjectId(objective_id.get_identifier())})

        obj_form = objects.ObjectiveForm(osid_object_map=result, runtime=self._runtime, proxy=self._proxy)
        self._forms[obj_form.get_id().get_identifier()] = not UPDATED

        return obj_form