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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 clean(self, tool):
 """ Clean a project """


        tools = self._validate_tools(tool)
        if tools == -1:
            return -1

        for current_tool in tools:
            # We get the export dict formed, then use it for cleaning
            self._fill_export_dict(current_tool)
            path = self.project['export']['output_dir']['path']

            if os.path.isdir(path):
                logger.info("Cleaning directory %s" % path)

                shutil.rmtree(path)
        return 0