[Tutor] Problems changing a list item in place ?

[Andy W]

> Hello all,
>     I have a program with a two-dimensional list called map.  After it has
already been populated, I want to do this:
>
>      map[y_box][x_box][0] = selected_tile
>
>      But I get this error:
>
>    File "map_edit.py", line 270, in main
>     map[y_box][x_box][0] = selected_tile                        # Change
value of the tile
> TypeError: object doesn't support item assignment

Could it be that  map[y_box][x_box] is referring to a tuple?
Tuples are immutable, so do not support item assignment.
If you make it so that the tuple is a list, then things should work.
Maybe I'm wrong though?

>
>   y_box and x_box are indexes; the statement "print map[y_box][x_box]"
works fine.  selected_tile is just an integer, though it shouldn't matter.
>
> I thought you could change list items in-place by assignment.  Are
multi-dimensional lists different?
>
> Thanks in advance,
> Chris
>
>
>
>
>
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