Python: unpacking into array elements -


why behavior of unpacking change when try make destination array element?

>>> def foobar(): return (1,2) >>> a,b = foobar() >>> (a,b)  (1, 2) >>> = b = [0, 0] # make , b lists >>> a[0], b[0] = foobar() >>> (a, b)  ([2, 0], [2, 0])

in first case, behavior expect. in second case, both assignments use last value in tuple returned (i.e. '2'). why?

when a = b = [0, 0], you're making both a , b point same list. because mutable, if change either, change both. use instead:

a, b = [0, 0], [0, 0]

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