**[Undeleted.](https://math.stackexchange.com/posts/4889065/timeline#history_b0e6b3da-bff0-49f7-adf2-619b387dec3f)**

Would you please undelete this post? [Existence of an $L^2$ function.](https://math.stackexchange.com/questions/4889065)? I found it interesting, but the asker deleted it just after receiving an answer.