How to iterate dictionaries using for loops in Python
With for loops, we can iterate a dictionary by key, value or both of them:
By key:
>>> d = {'a':12, 'b':2, 'c':21}
>>> for key in d:
print(key, end=' ')
a b c
>>>
By value:
>>> for value in d.values():
print(value, end=' ')
12 2 21
>>>
By both key and value:
>>> for key, value in d.items():
print(key+ ":"+ str(value))
a:12
b:2
c:21
>>>
Caveat, please check the following code:
>>> for key in d:
print(key + ':' + str(d[key]))
a:12
b:2
c:21
>>>
It does the same thing as the d.items() code, but d[key] inside a for loop caused the keys to be hashed again, which is not efficient if the dictionary is large.
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