How can I check if an object is an iterator in Python?

Question

I can check for a next() method, but is that enough? Is there an ideomatic way?

Answer 1

answer from python sourcecode doc comments:

{python install path}/Versions/3.5/lib/python3.5/types.py

# Iterators in Python aren't a matter of type but of protocol.  A large
# and changing number of builtin types implement *some* flavor of
# iterator.  Don't check the type!  Use hasattr to check for both
# "__iter__" and "__next__" attributes instead.