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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 grading_status_text(self):
        '''
        A rendering of the grading that is an answer on the question
        "Is grading finished?".
        Used in duplicate view and submission list on the teacher backend.
        '''
        if self.assignment.is_graded():
            if self.is_grading_finished():
                return str('Yes ({0})'.format(self.grading))
            else:
                return str('No')
        else:
            return str('Not graded')