public Optional<Ref<ParameterObject>> getHeader(String header) {
        for (Map.Entry<String, Ref<ParameterObject>> entry : headers.entrySet()) {
            if (entry.getKey().equalsIgnoreCase(header)) {
                return Optional.of(entry.getValue());
            }
        }

        return Optional.empty();
    }
Gets a header by case-insensitive header name.

@param header Header to retrieve.
@return Returns the optionally found header.
smithy-openapi/src/main/java/software/amazon/smithy/openapi/model/ResponseObject.java