python collections.defaultdict() compile error
The following code, simple and clear enough, produces an error when compiled:
import string
import collections
#create dictionary with alphabets as keys, and empty values
list = ['aema', 'airplane', 'amend']
gen_dict = dict.fromkeys(string.ascii_lowercase, '')
gen_dict = collections.defaultdict(list)
for x in list:
gen_dict['a'].append(x)
and the error produced is:
Traceback (most recent call开发者_运维技巧 last):
File "indexdict.py", line 14, in <module>
gen_dict = collections.defaultdict(list)
TypeError: first argument must be callable
any idea? thanks in advance
you overwrite the internal list
, being the name of a type, with your list = ['aema', 'airplane', 'amend']
above. Rename your list
to e.g. keys
or keylist
and all will be fine.
So replace
list = ['aema', 'airplane', 'amend']
with
keys = ['aema', 'airplane', 'amend']
and
for x in list:
with
for x in keys:
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