_edd_privacy_get_customer_id_for_email() – Since our eraser callbacks need to look up a stored customer ID by hashed email address, developers can use this to retrieve the customer ID associated with an email address that’s being requested to be deleted even after the customer has been anonymized.
_edd_privacy_get_payment_action() – Given an EDD_Payment, determine what action should be taken during the eraser processes.
EDD_Amazon_Payments::check_config() – Show an error message on checkout if Amazon is enabled but not setup.
EDD_Amazon_Payments::disable_address_requirement() – Removes the requirement for entering the billing address
EDD_Amazon_Payments::get_amazon_authenticate_redirect() – Retrieve the return URL for Amazon after authentication on Amazon is complete
EDD_Amazon_Payments::get_amazon_checkout_uri() – Retrieve the checkout URL for Amazon after authentication is complete
EDD_Amazon_Payments::get_amazon_signin_redirect() – Retrieve the URL to send customers too once sign-in is complete
EDD_Amazon_Payments::is_setup() – Method to check if all the required settings have been filled out, allowing us to not output information without it.
EDD_Amazon_Payments::link_transaction_id() – Given a transaction ID, generate a link to the Amazon transaction ID details
EDD_Amazon_Payments::maybe_hide_gateway_select() – Hides payment gateway select options after return from Amazon
edd_apply_preset_discount() – Applies the preset discount, if any. This is separated from edd_listen_for_cart_discount() in order to allow items to be added to the cart and for it to persist across page loads if necessary
