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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_assessment_taken(self, assessment_taken_id):
 """Gets the ``AssessmentTaken`` specified by its ``Id``. In plenary mode, the exact ``Id`` is found or a ``NotFound`` results. Otherwise, the returned ``AssessmentTaken`` may have a different ``Id`` than requested, such as the case where a duplicate ``Id`` was assigned to an ``AssessmentTaken`` and retained for compatibility. arg: assessment_taken_id (osid.id.Id):
 ``Id`` of the ``AssessmentTaken`` return: (osid.assessment.AssessmentTaken) - the assessment taken raise: NotFound - ``assessment_taken_id`` not found raise: NullArgument - ``assessment_taken_id`` is ``null`` raise: OperationFailed - unable to complete request raise: PermissionDenied - authorization failure occurred *compliance: mandatory -- This method is must be implemented.* """

        # Implemented from template for
        # osid.resource.ResourceLookupSession.get_resource
        # NOTE: This implementation currently ignores plenary view
        collection = JSONClientValidated('assessment',
                                         collection='AssessmentTaken',
                                         runtime=self._runtime)
        result = collection.find_one(
            dict({'_id': ObjectId(self._get_id(assessment_taken_id, 'assessment').get_identifier())},
                 **self._view_filter()))
        return objects.AssessmentTaken(osid_object_map=result, runtime=self._runtime, proxy=self._proxy)