# https://technology.jana.com/2016/04/26/challenge-your-python-knowledge/
# 1 - iterator object evals as true, but is empty
mystery = iter('')

# 2 - double precision does not allow counting in 1-increments up to inf.
# probably something like 1e18 could be enough that x+1 == x
mystery1 = 1
mystery2 = 1e308

# 3 - self-referential dict
mystery1 = {}
mystery2 = {}
mystery1['self'] = mystery1
mystery2['self'] = mystery2