Admin column callback example

admin-column-callback.php

/**
 * Show formated date from post meta in admin columns
 *
 * $meta_key - custom field to get date from
 * $format   - date format
 */
function jet_admin_column_date( $column, $post_id ) {

	$meta_key = '_date';
	$format = 'F, j Y';
	$date   = get_post_meta( $post_id, $meta_key, true );

	if ( ! $date ) {
		return '--';
	} else {
		return date_i18n( $format, $date );
	}

}

Hi, please may i know how to get the meta key in Callback column just like jet_engine_custom_cb_related_posts?
Example i would like to achieve like this
set custom callback as >>> my_custom_admin_callback::my_meta_key
Then i create function

function my_custom_admin_callback( $column, $post_id, $meta_key ) {
/*So i can directly use the meta_key*/
}