'str' object does not support item assignment

[jimbo1qaz]

On Sunday, September 23, 2012 11:31:41 AM UTC-7, jimbo1qaz wrote:
> spots[y][x]=mark fails with a "'str' object does not support item assignment" error,even though:
> 
> >>> a=[["a"]]
> 
> >>> a[0][0]="b"
> 
> and:
> 
> >>> a=[["a"]]
> 
> >>> a[0][0]=1000000
> 
> both work.
> 
> Spots is a nested list created as a copy of another list.

Yeah, it's a recursive function. Like it makes a difference.