blog post not lists in admin area

[SharonLandis]

My site has two blogs / feed pages: blog and podcast

The podcast page only lists post with category id 7 through a custom field query_args => cat=7.
I couldn't get the blog page to exclude cat id 7 (query_args => cat=-7) using a custom field, instead I used php from another post on this forum:
// Exclude categories from blog archive.
add_action( 'pre_get_posts', 'exclude_categories_blog' );
function exclude_categories_blog ( $query ) {
if( $query->is_main_query() ) {
$query->set( 'cat', '-7' );
}
}

In the backend admin area, cat id 7 posts don't show up in the list of posts.

How do I modify the above php to show cat 7 posts for the admin area?

Thanks!

http://slandisconsulting.com

[SharonLandis]

updated php to
if( !is_admin() && $query->is_main_query() )

Works like a charm

[Author]

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