Untitled

Code
dbname1 = "rdsbmsperf"
        dbuser1 = "rdsbmsperf"
        dbpassword1 = "rdsbmsperf"

When I do this:
cmds.append(
            f"engine_public_version=$(/rdsdbbin/oscar/bin/mysql --user={dbuser1} --database={dbname1} -e \"SELECT aurora_version();\" --password={dbpassword1} | grep -oP '[\\d.]+' | tr -d '\\n')"
        )

Why does it come empty, can you give me correct code?