Errors thrown from here are not handled

Question

A possibly thrown error in let jsonData = try JSONSerialization ... is not handled.

You can ignore a possible error, and crash as penalty if an error occurs:

let jsonData = try! JSONSerialization ...

or return an Optional, so jsonData is nil in error case:

let jsonData = try? JSONSerialization ...

or you can catch and handle the thrown error:

do {
    let jsonData = try JSONSerialization ...
    //all fine with jsonData here
} catch {
    //handle error
    print(error)
}

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