05handler.py

import logging

logger = logging.getLogger(__name__)

mapping = {
    "TRACE": "[ trace ]",
    "DEBUG": "[ \x1b[0;36mdebug\x1b[0m ]",
    "INFO": "[  \x1b[0;32minfo\x1b[0m ]",
    "WARNING": "[  \x1b[0;33mwarn\x1b[0m ]",
    "WARN": "[  \x1b[0;33mwarn\x1b[0m ]",
    "ERROR": "\x1b[0;31m[ error ]\x1b[0m",
    "ALERT": "\x1b[0;37;41m[ alert ]\x1b[0m",
    "CRITICAL": "\x1b[0;37;41m[ alert ]\x1b[0m",
}


class ColorfulHandler(logging.StreamHandler):
    def emit(self, record: logging.LogRecord) -> None:
        record.levelname = mapping[record.levelname]
        super().emit(record)


logging.basicConfig(handlers=[ColorfulHandler()], level=logging.DEBUG)

logger.debug("hello")
logger.info("hello")
logger.warning("hello")
logger.error("hello")
logger.critical("hello")

main.go

package main

import (
	"log"
	"os"

	"github.com/comail/colog"
)

// https://github.com/comail/colog

func main() {
	colog.Register()
	colog.SetOutput(os.Stdout)
	colog.ParseFields(true)
	colog.SetFlags(log.Ldate | log.Lshortfile)

	log.Print("trace: logging this to stdout")
	log.Print("debug: logging this to stdout")
	log.Print("info: logging this to stdout")
	log.Print("warning: with fields foo=bar")
	log.Print("error: with fields foo=bar")
	log.Print("alert: with fields foo=bar")
}

output.txt

[ trace ] 2020/03/01 main.go:18: logging this to stdout
[ debug ] 2020/03/01 main.go:19: logging this to stdout
[  info ] 2020/03/01 main.go:20: logging this to stdout
[  warn ] 2020/03/01 main.go:21: with fields  foo=bar
[ error ] 2020/03/01 main.go:22: with fields  foo=bar
[ alert ] 2020/03/01 main.go:23: with fields  foo=bar