public function column_admins( $network ) {
		$network_admins = (array) get_network_option( $network->id, 'site_admins', array() );
		$network_admins = ! empty( $network_admins ) ? array_filter( $network_admins ) : array();

		// Concatenate for markup.
		echo empty( $network_admins ) ? esc_html( join( ', ', $network_admins ) ) : esc_html( '&mdash;' );
	}