[Python] Python's collections.defaultdict returns default value correctly unless the key isn't...

Basically if I set a defaultdict and reference it by key it will work fine and return the value that I set as default. However if I use a .get() on it the default value is not returned. Here is the simplest example I can give of it.

basedict = defaultdict(dict)
assert(basedict['junk'] == {}) # Pass
assert(basedict.get('junk') == {}) # Pass
assert(basedict.get('popcorn') == {}) # Fail


For completion, I was working with dicts of dicts and my code where I initially encountered the problem looked a bit more like this

from collections import defaultdict

basedict = defaultdict(dict)
assert(basedict['junk'] == {})

basedict[69] = defaultdict(lambda: 1000)
assert(basedict[69]['junk'] == 1000)
assert(basedict[69].get('junk') == 1000)
assert(basedict[69].get('junk', 420) == 1000)

# The above works fine, but if I call .get on a default dict using a key I've
# never referenced before it returns None or the .get supplied default value
assert(basedict[69].get('garbage') == 1000) # Returns None
assert(basedict[69].get('garbage', 420) == 1000) # Returns 420
assert(basedict[69].get('dumpster', 420) == 1000) # Returns 420

# But if I place a an assert before the calling .get(garbage) that
# checks basedict[69]['garbage'] then the asserts after work until I get
# to 'dumpster' at which point it fails again
# It also fails if I set the defaultdict to something other than a lambda
basedict[7] = defaultdict(dict)
assert(basedict[7]['taco'] == {}) # Pass
assert(basedict[7].get('taco') == {}) # Pass
assert(basedict[7].get('burrito') == {}) # Fail

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