Hello,
I was wondering why, in the code below, dictionary 'a' can be populated while
dictionary 'b' can't.
b.get(k, []) will not return the default value [], but 'None' if k is not
present in 'b'. Why?
Of course, one could use try-except to do this, but I'd just like to understand
why the .get() version does not work.
Thanks!
import random
a = {}
for i in range(100):
k = random.randint(1, 10)
a[k] = a.get(k, 0) + 1
print a
b = {}
process = lambda k: k**2
for i in range(100):
k = random.randint(1, 10)
v = process(k)
b[k] = b.get(k, []).append(v) # <--- error!
print b
Regards,
Albert-Jan
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