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What is the PEP8 correct way for long method's name? I have a unit test with a self-describing method:
def success_if_buying_price_item_when_participating_and_progression_is_100_percent(self):
But unfortunately this (too long?) method reaches the 80 characters line limit.
Should I rename it and add a description in code or there is an other way?
Yes, rename it and add a description. This code is dangerous, one could fall from its chair while another could have a heart attack. Please, rename that ASAP, you don't want to feel responsible.