Data received from Network architecture.kt

data class PractitionersModel(val data: Any)

object Network {
    fun requestPracticioners(onSuccess: (PractitionersModel) -> Unit, onError: (Throwable) -> Unit)
    {
        // типа сетевой запрос
    }
}

interface Activity {
    val adapter: Adapter
    
    fun onCreate() {
        Network.requestPracticioners(onSuccess = {practicioners ->
            adapter.setPracticioners(practicioners)
        }, onError = {
            displayError(it)
        })
    }
    fun displayError(it: Throwable)
}

interface Adapter {
    fun setPracticioners(practicioners: PractitionersModel)
}