what the heck this code is doing?

[Basant Dagar]

#See below code:

def lookup(d, keyval):
    found = False
    for child in d:
        if found : return child.text
        if child.tag == 'key' and child.text == keyval :
            found = True
    return None

trackID = lookup(entry, 'Track ID')

 
Below is the main part of input xml file data, it passes to lookup function:

<key>Track ID</key><integer>369</integer>

what I don't get is. How in the world it returns value 369 for the variable 
'trackID'??
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