Doc: fix example for iter() function. (GH-11959)


read() returns bytes for a file opened in binary mode,
so b'' should be used as a sentinel instead of ''.
Otherwise the loop will be infinite.
(cherry picked from commit 11fa0e48a958716186eb99348a46064e944eccf6)

Co-authored-by: Cristian Ciupitu <cristian.ciupitu@yahoo.com>
1 file changed