REST API GuidecouponsGet couponGet coupon GET /coupons/:ID Return the data of an existing coupon by ID. Requires pricelists permission. Request Responses200304401403404500OKResponse HeadersETagEntity tag (RFC 7232)Last-ModifiedLast modification date and time (RFC 7231)Not ModifiedUnauthorizedResponse HeadersWWW-AuthenticatePreferred authentication scheme (RFC 7235)ForbiddenNot FoundRuntime Error (Internal Server Error)