def _peek_unlocked(self, n=0):
        want = min(n, self.buffer_size)
        have = self._read_pos - len(self._read_buf)
        if have < want:
            to_read = self.buffer_size - have
            current = self.raw.read(to_read)
            if current:
                self._read_buf = self._read_buf[self._read_pos:] + current
                self._read_pos = 0
        return self._read_buf[self._read_pos:]
dataset/ETHPy150Open deanhiller/databus/webapp/play1.3.x/python/Lib/io.py/BufferedReader._peek_unlocked/swapped operands of `-`