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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 encode_bytes(self):
 """This method encodes the QR code's data if its mode is 8 bit mode. It returns the data encoded as a binary string. """

        with io.StringIO() as buf:
            for char in self.data:
                if not isinstance(char, int):
                    buf.write('{{0:0{0}b}}'.format(8).format(ord(char)))
                else:
                    buf.write('{{0:0{0}b}}'.format(8).format(char))
            return buf.getvalue()