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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 find_course_and_crosslistings(self, partial):
 """Returns the given course and all other courses it is crosslisted with. """

        course = self.find_course(partial)
        crosslisted = self.crosslisted_with(course.crn)
        return (course,) + tuple(map(self.find_course_by_crn, crosslisted))