Why not enforce four space indentations in version 3.x?

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    JM> By the way why would you prevent us from using tabs for indenting ?
    JM> If I'm not wrong, from a semantic point of view, that's what tabs
    JM> are for: indenting. Spaces are meant to separate tokens, aren't they
    JM> ?  I love my tabs, don't take them away from me !

I don't think your tabs have been taken away, you just can't mix them with
spaces.

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