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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 readBytes(self):
 """ Reads and returns a utf-8 encoded byte array. """

        length, is_reference = self._readLength()

        if is_reference:
            return self.context.getString(length)

        if length == 0:
            return ''

        result = self.stream.read(length)
        self.context.addString(result)

        return result