to change the name (i.e WPPizza) in the WP admin/backend just add define('WPPIZZA_NAME', 'The Name You Want'); to your wp-config.php anywhere before /* That's all, stop editing! Happy blogging. */

i.e. – add to /edit your wp-config.php to be something like

define('WPPIZZA_NAME', 'My Shop');
/* That's all, stop editing! Happy blogging. */

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