This contains the Response of a request and a cancel method
On making a request, it returns the Cancellable object immediately
without waiting for the request to complete.
The user can cancel the request by calling the cancel method
before the response arrives. It is safe to call the cancel method,
even after the response arrives. In that case, the cancel method will
do nothing.
This class contains the response details of a request
This includes the status of the response
The data or the parsed body of the response
The error if the request failed or the parsing failed
and hasError which is true if the error is not null
and isCancelled which is true if the request was cancelled by the user.
If the request gets cancelled by the user, the data and error will
be null, and the status will be -1.