Autogenerated student number instead of username in Wordpress

My friend did a custom PHP code to generate a "student number" on my website instead of the regular generated username. So users get a consecutive student number when they sign-up instead of the random username. Unfortunately, each time I upgrade wordpress the code is gone and I have to manually edit the files again and add his code. So I want a developer to take the code my friend did and install it in a way it will survive over Wordpress upgrades. Can you make a plug-in? Please mention my name: Ishi, so I see you have read the description of this project. This is the code: There two two code modifications. The first is to the checkout function of woo commerce. The second is a modification to the add-user function within Word Press. I assumed you’d have two possible ways that users would be added into the system, the first through a website purchase thus the modification of [login to view URL] which is located under wp-content/plugins/woocommerce/includes/, the second is through the admin function of wordpress, it’s a file called [login to view URL], that’s under the directory wp-admin. For [login to view URL], the following needs to be done. 1 - Search for // Customer Accounts (should be line 606). 2 - Comment out $username = ! empty( $this->posted['account_username'] ) ? $this->posted['account_username'] : ‘'; 3 - Insert the following code just after that line //Hussain modification global $wpdb; $result = $wpdb->get_var( "SELECT * FROM {$wpdb->users} WHERE ID=(SELECT MAX(ID) FROM {$wpdb->users})"); $result += 17001; $local_username = 'sk'.$result; // End of Hussain mod 4 - Comment out this line //$new_customer = wc_create_new_customer( $this->posted['billing_email'], $usrname, $password ); 5 - Replace with: $new_customer = wc_create_new_customer( $this->posted['billing_email'], $local_username, $password ); 6 - search for reference to display_name, replace the variable that’s after => to be $local_username For [login to view URL] make the following changes: 1 - search for line $creating = isset( $_POST['createuser'] ); (it should be line 383) 2 - Comment out this line $new_user_login = $creating && isset( $_POST['user_login'] ) ? wp_unslash( $_POST['user_login'] ) : ‘'; 3 - Replace with //Hussain modification global $wpdb; $result = $wpdb->get_var( "SELECT * FROM {$wpdb->users} WHERE ID=(SELECT MAX(ID) FROM {$wpdb->users})"); $result += 17001; $new_user_login = 'SK'.$result; // End of Hussain mod