local scope in comps and gen exps

local_scope_in_comps_genexps.py

#!/usr/bin/env python3

x = "EGG"
codes = [ord(x) for x in x]

print(codes)
# output: [69, 71, 71]

print(x)
# x is not clobbered, still bound to 'EGG'
# output: EGG


codes = [last := ord(c) for c in x]

print(last)
# `last` remains
# output: 71

print(c)
# but `c` is gone; it only existed inside the listcomp
# output: NameError: name 'c' is not defined