5.28.0
(feat): Add respect_optional_request_body. With it enabled, an endpoint whose request body the API does
not require defaults that body to the OMIT sentinel — batch_refund(request: Sequence[RefundRequest] = OMIT)
rather than request: Optional[Sequence[RefundRequest]] — so “not passed” stays distinct from an
explicit None, and a body left out means the request carries no content and no Content-Type.
Examples that supply no body render as client.batch_refund(). When the body inlines into keyword
arguments instead, leaving all of them out sends no body rather than an empty {}. Defaults to
false, so signatures and snippets are unchanged until you opt in.