feed.entry is property of feed and it’s value is (if it’s not, this code will fail) object implementing iteration protocol (array, for example) and has iter method, which returns iterator object
Iterator has next() method, returning next element or raising exception, so python for loop is actually:
iterator = feed.entry.__iter__()
while True:
try:
party = iterator.next()
except StopIteration:
# StopIteration exception is raised after last element
break
# loop code
print party.location.address.text