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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 open(self, file_path):
 """ Open an Excel workbook file. :param str file_path: Excel workbook file path to open. """


        if self.is_opened() and self.workbook.file_path == file_path:
            self._logger.logger.debug("workbook already opened: {}".format(self.workbook.file_path))
            return

        self.close()
        self._open(file_path)