Difference between dict.clear() and assigning {} in Python

d = {} will create a new instance for d but all other references will still point to the old contents. d.clear() will reset the contents, but all references to the same instance will still be correct.

If you have another variable also referring to the same dictionary, there is a big difference:

>>> d = {"stuff": "things"}
>>> d2 = d
>>> d = {}
>>> d2
{'stuff': 'things'}
>>> d = {"stuff": "things"}
>>> d2 = d
>>> d.clear()
>>> d2
{}

This is because assigning d = {} creates a new, empty dictionary and assigns it to the d variable. This leaves d2 pointing at the old dictionary with items still in it. However, d.clear() clears the same dictionary that d and d2 both point at.