Checking if XML has been read

I have an XML document on a URL which is read by a service every day.

The problem is the service reads the XML at random times and I want to know at what time the XML was read.

My questions are:

1. How can I check if the service has read the XML for today?


2. How can I know what time it was read?


3. Is there a way to detect what parts of the XML were read?

P.S I'm using python.

Thanks all,