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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 app_evaluation_count(app_id, value=1):
        '''
        Get the Evalution sum.
        '''
        return TabEvaluation.select().where(
            (TabEvaluation.post_id == app_id) & (TabEvaluation.value == value)
        ).count()