[issue31614] can't list groupby generator without breaking the sub groups generators

Loïc Le Loarer added the comment: Thanks a lot for the clear answer, sorry for not having read the online documentation, I only read the help(itertools.groupby) which has much less details. And for my use case, I can use an explicit command just to compute the number of groups

[issue31614] can't list groupby generator without breaking the sub groups generators

New submission from Loïc Le Loarer : If I "list" the itertools groupby generator, then the sub generators of each groups are all empty except the last one. import itertools as i L = ['azerty','abcd','ac','aaa','z','