How to use the txaio.interfaces.log_levels function in txaio

def emit(self, level, *args, **kwargs):

        if log_levels.index(self._log_level) < log_levels.index(level):
            return

        if level == "trace":
            return self._trace(*args, **kwargs)

        level = LogLevel.lookupByName(level)
        return self._log(level, *args, **kwargs)

def emit(self, level, *args, **kwargs):

        if log_levels.index(self._log_level) < log_levels.index(level):
            return

        if level == "trace":
            return self._trace(*args, **kwargs)

        level = LogLevel.lookupByName(level)
        return self._log(level, *args, **kwargs)

def _acceptable_level(self, level):
        if self._levels is None:
            target_level = log_levels.index(_log_level)
            self._levels = [
                self.to_tx[lvl]
                for lvl in log_levels
                if log_levels.index(lvl) <= target_level and lvl != "none"
            ]
        return level in self._levels

def _set_level(self, level):
        target_level = log_levels.index(level)
        # this binds either _log or _no_op above to this instance,
        # depending on the desired level.
        for (idx, name) in enumerate(log_levels):
            if idx < target_level:
                log_method = functools.partial(_log, self, name)
            else:
                log_method = _no_op
            setattr(self, name, log_method)

def _acceptable_level(self, level):
        if self._levels is None:
            target_level = log_levels.index(_log_level)
            self._levels = [
                self.to_tx[lvl]
                for lvl in log_levels
                if log_levels.index(lvl) <= target_level and lvl != "none"
            ]
        return level in self._levels

def __init__(self, **kwargs):
            self.namespace = kwargs.get('namespace', None)
            if _loggers is not None:
                _loggers.append(weakref.ref(self))
            # this class will get overridden by _TxLogger below, so we
            # bind *every* level here; set_log_level will un-bind
            # some.
            for name in log_levels:
                setattr(self, name, partial(self._do_log, name))

def start_logging(out=_stdout, level='info'):
    """
    Begin logging.

    :param out: if provided, a file-like object to log to. By default, this is
                stdout.
    :param level: the maximum log-level to emit (a string)
    """
    global _log_level, _loggers, _started_logging
    if level not in log_levels:
        raise RuntimeError(
            "Invalid log level '{0}'; valid are: {1}".format(
                level, ', '.join(log_levels)
            )
        )

    if _started_logging:
        return

    _started_logging = True
    _log_level = level

    handler = _TxaioFileHandler(out)
    logging.getLogger().addHandler(handler)
    # note: Don't need to call basicConfig() or similar, because we've
    # now added at least one handler to the root logger
    logging.raiseExceptions = True  # FIXME
    level_to_stdlib = {
        'critical': logging.CRITICAL,

def _set_log_level(self, level):
        target_level = log_levels.index(level)
        # this binds either _log or _no_op above to this instance,
        # depending on the desired level.
        for (idx, name) in enumerate(log_levels):
            if idx <= target_level:
                log_method = functools.partial(_log, self, name)
            else:
                log_method = _no_op
            setattr(self, name, log_method)
        self._log_level = level

def _acceptable_level(self, level):
        if self._levels is None:
            target_level = log_levels.index(_log_level)
            self._levels = [
                self.to_tx[lvl]
                for lvl in log_levels
                if log_levels.index(lvl) <= target_level and lvl != "none"
            ]
        return level in self._levels