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Taras Banakh
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A metrizable example can be construct as follows. In the plane consider the subset $$X:=\big\{(x,\tfrac{2k+1}{2^n}):k,n\in\mathbb Z,\;x\in\mathbb R\setminus \tfrac1{2^n}\mathbb Z\big\}.$$

It is clear that $X$ contain (countably many) topological copies of the real line. By a back-and-forth argument (a bit tricky) it can be shown that any non-empty open subset of $X$ is homeomorphic to $X$.

Taras Banakh
  • 42k
  • 3
  • 74
  • 184