With more than 1 level of generic type, the "closure" of generic
parameters would get tokenized by python as a single right shift (>>)
rather than two gt (>, >) leading to our own tokenizing pass getting
lost and blowing up.
Fix by explicitly recognizing and splitting (>>) into (>, >). We could
consider writing the entire tokenizer ourselves instead of
post-processing Python's but given the entire post-processing function
is currently shorter than just Pythons' tokenizer's regexes...
Anyway issue found by vsc while trying to write better docstrings.
Xavier Morel
f1143b4073