Ory is the largest open source community in the world for cloud software application security. We maintain advanced open source security software solving authentication, authorization, access control, application network security, and delegation. Ory implements a variety of industry and best-practice standards including OAuth 2.0 / OAuth 2.1, OpenID Connect, Zero Trust Networking, Google Zanzibar Policy Framework, FIDO2 U2F, WebAuthn, TOTP, and more.

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```type AuthenticationSession struct {
  Subject      string
  Extra        map[string]interface{}
  Header       http.Header
  MatchContext MatchContext
}```
In particular, how to discover the contents of `Extra` ?