Not only that, but look at the niche Python is occupying. It's a well established and respected niche to which, by definition, the language is suited very well.
By adding static types, the focus of the language would move to a different niche, which would probably be already occupied by some competitor language(s) which do(es) types much better.
If you want sort-of Python-ish syntax with elaborate types, just use Nimrod and leave Python alone. Get the right tool for the job, don't mutilate a perfectly good existing tool.
What exact niche is that? Unless you mean "dynamically typed" (in which case that begs the question), I don't know what niche you think it couldn't occupy with static types. Not even arguing for static types: your comment is just really unclear.
By adding static types, the focus of the language would move to a different niche, which would probably be already occupied by some competitor language(s) which do(es) types much better.
If you want sort-of Python-ish syntax with elaborate types, just use Nimrod and leave Python alone. Get the right tool for the job, don't mutilate a perfectly good existing tool.