log_to_console_and_file_in_jupyter.py

import logging
# w/o below lines with reloading `logging` no log file will be saved in Jupyter/IPython env, see here: https://stackoverflow.com/questions/31169540/python-logging-not-saving-to-file
from imp import reload
reload(logging)
from contextlib import redirect_stdout, redirect_stderr

LOG_FILE_NAME = 'log.txt'

# from https://stackoverflow.com/a/36296215
class StreamToLogger(object):
    """
    Fake file-like stream object that redirects writes to a logger instance.
    """
    def __init__(self, logger, log_level=logging.INFO):
        self.logger = logger
        self.log_level = log_level
        self.linebuf = ''

    def write(self, buf):
        temp_linebuf = self.linebuf + buf
        self.linebuf = ''
        for line in temp_linebuf.splitlines(True):
            # From the io.TextIOWrapper docs:
            #   On output, if newline is None, any '\n' characters written
            #   are translated to the system default line separator.
            # By default sys.stdout.write() expects '\n' newlines and then
            # translates them so this is still cross platform.
            if line[-1] == '\n':
                self.logger.log(self.log_level, line.rstrip())
            else:
                self.linebuf += line

    def flush(self):
        if self.linebuf != '':
            self.logger.log(self.log_level, self.linebuf.rstrip())
        self.linebuf = ''

# for logging both to console and file. Idea with handlers taken from here: https://stackoverflow.com/a/46098711
logging.basicConfig(
    level=logging.DEBUG,
    format='%(asctime)s:%(levelname)s:%(name)s: %(message)s',
    handlers=[
        logging.FileHandler(LOG_FILE_NAME),
        logging.StreamHandler()
    ],
)
# for logging to file only
# logging.basicConfig(
#     level=logging.DEBUG,
#     format='%(asctime)s:%(levelname)s:%(name)s: %(message)s',
#     filename=LOG_FILE_NAME,
#     filemode='a'
# )

stdout_logger = logging.getLogger('STDOUT')
sl_out = StreamToLogger(stdout_logger, logging.INFO)

stderr_logger = logging.getLogger('STDERR')
sl_err = StreamToLogger(stderr_logger, logging.ERROR)

with redirect_stdout(sl_out), redirect_stderr(sl_err):
    <put your code here>