Bitcoin Core's CLI has a converttopsbt command used to convert from raw transaction to PSBT transaction but how is it possible to convert from PSBT transaction to raw transaction using Bitcoin Core (or if not possible using another client like Electrum)?
Example of a PSBT transaction (testnet):
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