class Seahorse::Client::Configuration::DefaultResolver

def value_at(opt_name)
  value = @struct[opt_name]
  if value.is_a?(Defaults)
    # this config value is used by endpoint discovery
    if opt_name == :endpoint && @struct.members.include?(:regional_endpoint)
      @struct[:regional_endpoint] = true
    end
    resolve_defaults(opt_name, value)
  else
    value
  end
end