Example of a homeomorphism between a doughnut and a coffee cup
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Витамин D.Чем опасен дефицит витамина D и почему он так нужен организму?12 мая 2023
Different syntax, same results. For somebody familiar with SQL, Postgres variation is probably easier to grasp, but Mongo's query language is quite intuitive as well - it is JavaScript-like after all.