python - Explain the code function in call by object -


how y equal x call object no function call how work how y value change

y = [1, 2, 3] x = y x[:] = [-1]*3 print y [-1, -1, -1]

please explain happen in x , y , call object

y = [1, 2, 3] x = y

x , y both point same list.

x[:] = [-1]*3

that list modified, way of assignment whole-object-slice (see here).

print y # [-1, -1, -1]

the modified list printed console.

and way: there no "call object". assignment slice (which, noted in link, modifies object).


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