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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 get_blog_context(context):
 """ Get context data useful on all blog related pages """

    context['authors'] = get_user_model().objects.filter(
        owned_pages__live=True,
        owned_pages__content_type__model='blogpage'
    ).annotate(Count('owned_pages')).order_by('-owned_pages__count')
    context['all_categories'] = BlogCategory.objects.all()
    context['root_categories'] = BlogCategory.objects.filter(
        parent=None,
    ).prefetch_related(
        'children',
    ).annotate(
        blog_count=Count('blogpage'),
    )
    return context