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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 init_config(self, app):
 """Initialize config."""

        app.config.setdefault(
            'LOGGING_FS_LEVEL',
            'DEBUG' if app.debug else 'WARNING'
        )
        for k in dir(config):
            if k.startswith('LOGGING_FS'):
                app.config.setdefault(k, getattr(config, k))

        # Support injecting instance path and/or sys.prefix
        if app.config['LOGGING_FS_LOGFILE'] is not None:
            app.config['LOGGING_FS_LOGFILE'] = \
                app.config['LOGGING_FS_LOGFILE'].format(
                    instance_path=app.instance_path,
                    sys_prefix=sys.prefix,
                )