Call to a Custom Auth Function

Currently, I am working on a Custom function authentication.
Could anyone help me how to call the function from my client as we have for the anonymous, emailPassword in https://docs.mongodb.com/realm/react-native/authenticate/

@Amiya_Panigrahi You should be able to use this method:
https://docs.mongodb.com/realm-sdks/js/10.0.0-beta.6/Realm.Credentials.html#.function