How to Retrieve Dictionary Keys as a List in Python 3 and Beyond
Unlike Python 2.7, which returns a list of keys when calling newdict.keys(), Python 3.3 and later returns a dict_keys object. While the dict_keys object behaves similarly to a list, it may not be desirable in certain situations where a plain list is preferred.
Getting a List of Keys with Python 3
To obtain a list of keys from a Python 3 dictionary, simply convert the dict_keys object to a list:
list(newdict.keys())
For example:
newdict = {1: 0, 2: 0, 3: 0} print(list(newdict.keys())) # Output: [1, 2, 3]
Considering Duck Typing
It's worth noting that the dict_keys object behaves like a list in many ways, such as supporting iteration:
for key in newdict.keys(): print(key) # Output: # 1 # 2 # 3
Therefore, unless specific use cases require a plain list, the dict_keys object may suffice.
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