First parameter is the steam community ID, second is the item serial, third is the player's name.
To fetch a user's name from the dictionary, both the ID and item serial must be provided. Use a serial of 0 or &bnsp to use an ID with a custom label, but no item serial.
If the serial is omitted, a link only to the inventory is generated.
If the third parameter is omitted, a default string of “Inventory” is displayed.