object ServingError{
// we are adding a method modification content method, to be used by the modification traits def modifyContent(error: ServingError, content: String): ServingError = {
error match {
case f: FatalError => FatalError(exceptionCause = f.exceptionCause, content = content)
case i: InvalidRequestError => InvalidRequestError(i.paramName, i.paramValue, content = content)
}
}
}