Beginner Python: is there a "cleaner" way to to rewrite my current code?

I am quite new to Python. Here I have written a code that translates alpha characters to numerics in a phone number. My code will just assume that the format of the phone number is entered correctly.

def phone(phone_number): converted_phone_number = "" for number in phone_number: if number in "ABC": converted_phone_number += '2' elif number in "DEF": converted_phone_number += '3' elif number in "GHI": converted_phone_number += '4' elif number in "JKL": converted_phone_number += '5' elif number in "MNO": converted_phone_number += '6' elif number in "PQR": converted_phone_number += '7' elif number in "TUV": converted_phone_number += '8' elif number in "WXYZ": converted_phone_number += '9' else: converted_phone_number += number return converted_phone_number def main(): print(phone("604-GOT-JUNK")) if __name__ == "__main__": main()