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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 _find_configs(self):
 """ Scans the project directory for config files or returns the explicitly specified list of files. """

        if self.config_files is not None:
            return self.config_files

        # Walk the whole project tree and look for "config.rb" files
        result = []
        for path, _, files in os.walk(self.app.root_path):
            if "config.rb" in files:
                result.append(os.path.join(path, "config.rb"))
        return result