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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 read_byte(self):
 """Read a byte."""

        if self.pos + 1 > self.remaining_length:
            return NC.ERR_PROTOCOL, None
        
        byte = self.payload[self.pos]
        self.pos += 1
        
        return NC.ERR_SUCCESS, byte