diff --git a/R/authenticate.R b/R/authenticate.R
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+++ b/R/authenticate.R
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+#' Set up the authentication with your API key
+#'
+#' @description
+#' Access to GPT-3's functions requires an API key that you obtain from [https://openai.com/api/](https://openai.com/api/). `gpt3.authenticate()` accepts your API key and ensures that you can connect to the models. `gpt3.endsession()` overwrites your API key _for this session_ (it is recommended that you run this when you are done). `check_apikey_form()` is a simple check if any information has been provided at all.
+#' @param apikey A character vector that is your personal API key
+#' @return A confirmation message
+#' @examples
+#' # Starting a session:
+#' gpt3.authenticate(apikey = 'REPLACE_THIS_WITH_YOUR_KEY')
+# '
+#' # After you are finished:
+#' gpt3.endsession()
+#' @export
+gpt3.authenticate = function(apikey){
+  api_key <<- apikey
+  print(paste0("Will use --> ", api_key, " for authentication."))
+}
+
+gpt3.endsession = function(){
+  api_key = "---"
+  print('-- session ended: you need to re-authenticate again next time.')
+}
+
+check_apikey_form = function(){
+
+  if(exists(x = 'api_key') == F){
+    warning("Use gpt3.authenticate() to set your API key")
+  } else if(nchar(api_key) < 10){
+
+    warning("Use gpt3.authenticate() to set your API key")
+
+  }
+}