Honestly - now that you know one language learning any new language is a pretty simple task. For example - here's a hello world in the three languages:

# Python
print("Hello, World!")

// Swift
print("Hello, World!")

// Rust
fn main() {
    println!("Hello, World!");
}

As you can see, the differences between Swift and Python are pretty minimal* and while rust adds a whole bunch of extra busywork (you need a function, you need an explanation point, you need a semicolon...) it's generally the same thing.

(*) While that comparison of Python/Swift only differs in the comments, Swift is generally a much more complex language than Python, so you will need to learn a bunch of new concepts. For example if you needed to manually specify the output string encoding you'd write the Swift hello world like this:

let string = "Hello, World!"
if let data = string.data(using: .utf16) {
    print(data)
}

There are some common Swift language patterns there that are rare in other languages:

• if let will gracefully handle any errors that occur in the encoding step (there can't be any errors when you're using utf16 encoding, but if another encoding format was specified it might fail if, for example, you gave it an emoji.
• Swift allows you to interleave part of your function names in between the function arguments. That's not a data() function, the function name is data(using:) and there are other function names that start with data() but accept totally different arguments, for example you might give it a URL and it would download the contents of the URL as the contents of the data.
• the .utf16 syntax is also something I haven't seen elsewhere. The using parameter only accepts String.Encoding.something and you can shortcut that by only writing the .something part.

For completeness, in python and rust you would do:

# python
string = "Hello, World!"
utf16_data = string.encode("utf-16")
print(utf16_data)

# rust
fn main() {
    let string = "Hello, World!";
    let utf16_data: Vec< u16 > = string.encode_utf16().collect();
    println!("{:?}", utf16_data);
}

That's actually pretty good comparison of the three languages and an example of why I like Swift.

The syntax in Rust is absurdly complicated for such a simple task. And while the Python code is very simple, it doesn't handle potential encoding errors as gracefully as Swift, and it also uses a string to specify the encoding, which opens up potential mistakes if you make a simple typo an also you'll have to do a Google search to check - is it "utf-16" or "utf16"? With Swift the correct encoding string will auto-complete and it will fail to compile if you make a mistake.