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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 tutor_courses(self):
        '''
            Returns the list of courses this user is tutor or owner for.
        '''
        tutoring = self.user.courses_tutoring.all().filter(active__exact=True)
        owning = self.user.courses.all().filter(active__exact=True)
        result = (tutoring | owning).distinct()
        return result