That's a great question. At issue, in your code, ilo is an IndexList object. Within that object is the metadata and index list. The current actionable list of indices can be accessed with .indices:
print(ilo.indices)
However, that will print as a list:
['index1', 'index2', 'index3',...'indexN']
If you want them printed on a single line, you'd have to loop through them:
for idx in ilo.indices:
print(idx)
You may even want them sorted alphabetically:
for idx in sorted(ilo.indices):
print(idx)