We will use the flapi module to communicate with Flickr. It provides access to the API methods. Most large-scale companies implement some level of authorization. In other words, we can't just make a request and upload/retrieve data. We need to sign in our requests with access tokens or provide credentials during the process. Flickr uses OAuth (1.0 specification), a type of standard for such operations. OAuth is an open standard for authorization and defines a method for clients to access server resources. Let's check the following diagram and see how Flickr's OAuth mechanism works:

Almost the entire process is wrapped in the flapi module. What we should remember here is that we need a Key and Secret to retrieve an access token. The same token will be used later when uploading the images.