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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 get_log_dir(self, conf_file):
 """Get watchdog log directory. Get watchdog log directory path configured in ``conf_file``. :returns: The watchdog log directory path. :returntype: str. :raises: IOError if ``conf_file`` is not readable. """

        log_dir = None

        with open(conf_file, 'r') as conf_f:
            for line in conf_f:
                line = line.split('#')[0].strip()

                try:
                    (key, value) = line.split('=', 1)
                    if key.strip() == 'log-dir':
                        log_dir = value.strip()
                except ValueError:
                    pass

        return log_dir