def valid_part?(api:, part:)
      rest_api = get(api)
      return true if rest_api.nil?
      rest_api.valid_part?(part)
    end
def valid_part?(api:, part:)
      rest_api = get(api)
      return true if rest_api.nil?
      rest_api.valid_part?(part)
    end
Given an API descriptor name and a single path part, returns `true` if the
 path part is valid for the given API. This method always returns `true` if
 the API is unknown.

 api  - the api descriptor name as a String
 part - the path part name as a String

 Returns `true` if the path part is valid for the API.