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// Add featured image on single post
add_action( 'genesis_before_entry', 'sk_display_featured_image' );
function sk_display_featured_image() {

	if ( ! is_singular( array( 'post', 'page' ) ) ) {
		return;
	}

	if ( ! has_post_thumbnail() ) {
		return;
	}

	// Display featured image above content
	echo '<div class="singular-featured-image">';
	genesis_image( array( 'size' => 'large' ) );
	echo '</div>';

}