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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 _readStreamHeader(self):
 """ Reads the magic header of a Java serialization stream :raise IOError: Invalid magic header (not a Java stream) """

        (magic, version) = self._readStruct(">HH")
        if magic != self.STREAM_MAGIC or version != self.STREAM_VERSION:
            raise IOError(
                "The stream is not java serialized object. "
                "Invalid stream header: {0:04X}{1:04X}".format(magic, version)
            )