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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 autodecode(self, a_bytes):
 """Automatically detect encoding, and decode bytes. """

        try:  # 如果装了chardet
            analysis = chardet.detect(a_bytes)
            if analysis["confidence"] >= 0.75:  # 如果可信
                return (self.decode(a_bytes, analysis["encoding"])[0],
                        analysis["encoding"])
            else:  # 如果不可信, 打印异常
                raise Exception("Failed to detect encoding. (%s, %s)" % (
                    analysis["confidence"],
                    analysis["encoding"]))
        except NameError:  # 如果没有装chardet
            print(
                "Warning! chardet not found. Use utf-8 as default encoding instead.")
            return (a_bytes.decode("utf-8")[0],
                    "utf-8")