[AstroPy] getting id value from xml files

[Grigoris Maravelias]

Hi to all!

I have a quick question with probably a rather straightforward answer
which probably may have slipped me.
What is the fastest way to call the value of a field id in an xml file
(produced by astropy).

For example to get the value from the ID 'sfr'
<INFO ID="sfr" name="sfr" value="1.34267351483e-40"/>

Best
Grigoris