text: from django.contrib import admin
  # <HINT> Import any new Models here
  from .models import Course, Lesson, Instructor, Learner, Question, Choice, Submission
  
  # <HINT> Register QuestionInline and ChoiceInline classes here
  class QuestionInLine(admin.StackedInline):
      model = Question
      extra = 5
  
  
  class ChoiceInLine(admin.StackedInline):
      model = Choice
      extra = 4
  
  
  class LessonInline(admin.StackedInline):
      model = Lesson
      extra = 5
  
  
  # Register your models here.
  class CourseAdmin(admin.ModelAdmin):
      inlines = [LessonInline,QuestionInLine]
      list_display = ('name', 'pub_date')
      list_filter = ['pub_date']
      search_fields = ['name', 'description']
  
  
  class LessonAdmin(admin.ModelAdmin):
      list_display = ['title']
  
  
  # <HINT> Register Question and Choice models here
  admin.site.register(Course, CourseAdmin)
  admin.site.register(Lesson, LessonAdmin)
  admin.site.register(Instructor)
  admin.site.register(Learner)
  
  
  class QuestionAdmin(admin.ModelAdmin):
      inlines = [ChoiceInLine]
  
  admin.site.register(Question, QuestionAdmin)
  admin.site.register(Choice)
  
  