def client(issuer)
      Faraday.new(url: issuer) do |f|
        f.use Faraday::Adapter::NetHttp
        f.headers['Accept'] = 'application/json'
      end
    end
def client(issuer)
      Faraday.new(url: issuer) do |f|
        f.use Faraday::Adapter::NetHttp
        f.headers['Accept'] = 'application/json'
      end
    end
init client