Use this method to set your Eyes license key.
To obtain your API key, see How to obtain your API key.
- A string that is your API Key.
- Type: void
Set this immediately after the Eyes object is created (before calling open). If you have an environment variable called APPLITOOLS_API_KEY that is set to the value of your API key, then you do not need to call this method, and Eyes will take the string from the environment value.