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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 save(self, path="speech"):
 """Save data in file. Args: path (optional):
 A path to save file. Defaults to "speech". File extension is optional. Absolute path is allowed. Returns: The path to the saved file. """

        if self._data is None:
            raise Exception("There's nothing to save")

        extension = "." + self.__params["format"]
        if os.path.splitext(path)[1] != extension:
            path += extension

        with open(path, "wb") as f:
            for d in self._data:
                f.write(d)

        return path