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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _logger(self):
 """Create TcEx app logger instance. The logger is accessible via the ``tc.log.<level>`` call. **Logging examples** .. code-block:: python :linenos: :lineno-start: 1 tcex.log.debug('logging debug') tcex.log.info('logging info') tcex.log.warning('logging warning') tcex.log.error('logging error') Args: stream_only (bool, default:False):
 If True only the Stream handler will be enabled. Returns: logger: An instance of logging """

        level = logging.INFO
        self.log.setLevel(level)

        # clear all handlers
        self.log.handlers = []

        # update logging level
        if self.default_args.logging is not None:
            level = self._logger_levels[self.default_args.logging]
        elif self.default_args.tc_log_level is not None:
            level = self._logger_levels[self.default_args.tc_log_level]
        self.log.setLevel(level)

        # add file handler if not already added
        if self.default_args.tc_log_path:
            self._logger_fh()

        # add api handler if not already added
        if self.default_args.tc_token is not None and self.default_args.tc_log_to_api:
            self._logger_api()

        self.log.info('Logging Level: {}'.format(logging.getLevelName(level)))