How can I add new keys to a dictionary?

python dictionary lookup
lfaraone picture lfaraone · Jun 22, 2009 · Viewed 3.8M times · Source

Is it possible to add a key to a Python dictionary after it has been created?

It doesn't seem to have an .add() method.

Answer

Paolo Bergantino picture Paolo Bergantino · Jun 22, 2009 
d = {'key': 'value'}
print(d)
# {'key': 'value'}
d['mynewkey'] = 'mynewvalue'
print(d)
# {'key': 'value', 'mynewkey': 'mynewvalue'}

you create a new key\value pair on a dictionary by assigning a value to that key. If the key doesn't exist, it's added and points to that value. If it exists, the current value it points to is overwritten. —R. Navega

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