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weakly Whyburn space; open function
We show that a (weakly) Whyburn space $X$ may be mapped continuously via an open map $f$ onto a non (weakly) Whyburn space $Y$. This fact may happen even between topological groups $X$ and $Y$, $f$ a homomorphism, $X$ Whyburn and $Y$ not even weakly Whyburn.
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