f-strings works on python IDLE but not on Sublime Text

I have just started reading the 2nd edition of Python Crash Course, and just in case someone has the book, I am on the subsection "Using Variables in Strings" in chapter 2.

The problem is, when I enter

first_name = "ada"
last_name = "lovelace"
full_name = f"{first_name} {last_name}"
print(full_name)

on Sublime Text, it is supposed to output

ada lovelace

but instead, I receive an error reading

  File "/Users/davidjiang/Code/Python/python_work/full_name.py", line 3
    full_name = f"{first_name} {last_name}"
                                          ^
SyntaxError: invalid syntax
[Finished in 0.1s with exit code 1]
[shell_cmd: python -u "/Users/davidjiang/Code/Python/python_work/full_name.py"]
[dir: /Users/davidjiang/Code/Python/python_work]
[path: /Library/Frameworks/Python.framework/Versions/3.8/bin:/Library/Frameworks/Python.framework/Versions/3.7/bin:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin]

I have already checked that Sublime Text is running in python3.7 by inserting

{ 
    "cmd": ["python3", "-u", "$file"], 
}

into the build system Python3.sublime-build. My terminal also runs in python3.

I also made sure that my code didn’t have any errors by finding and using this link explaining how to insert values into strings.
Additionally, the book I am reading comes with a collection of online resources complementing the course, including the code written at the beginning. When I put it through python IDLE, the code worked out fine.

Can someone please explain why the code doesn’t work on Sublime Text? Thanks in advance!

Edit: Apparently, my Sublime Text is running python2 instead of python3. As it seems that inputting the above code won’t work, does anyone have any advice on how to change Sublime to python3?

{
    "shell_cmd": "python3 -u "$file"",
    "file_regex": "^[ ]*File "(...*?)", line ([0-9]*)",
    "selector": "source.python",

    "env": {"PYTHONIOENCODING": "utf-8"},

    "variants":
    [
        {
            "name": "Syntax Check",
            "shell_cmd": "python3 -m py_compile "${file}"",
        }
    ]
}

{
"cmd": ["python3", "-i", "-u", "$file"],
"file_regex": "^[ ]File "(...?)", line ([0-9]*)",
"selector": "source.python" }