List top woocommerce customers by their total spent

wc_top_customers.php

<?php
function prefix_top_customers_with_total_spend( $length = 5 ) {
  if ( ! class_exists( 'woocommerce' ) ) {
		return;
	}
	$data      = [];
	$args      = [
		'role'   => 'customer',
		'number' => - 1,
		'fields' => 'ID'
	];
	$query     = new WP_User_Query( $args );
	$customers = $query->get_results();
	foreach ( $customers as $customer_id ) {
		$data[ $customer_id ] = wc_get_customer_total_spent( $customer_id );
	}
	arsort( $data );
	$data = array_slice( $data, 0, $length );

	return $data;
}