Print Product Id

Write code that examines a string stored in a variable called product_id and prints an appropriate version of the id. If the id is composed of only numeric digits, print it as is. If it is composed of a combination of alphabetic letters and digits, print the id with all alphabetic letters in uppercase. Otherwise (if there are any other type of characters in the id), print it with all alphabetic letters in lowercase. Assume that the product_id has already been initialized.