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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(self, size=-1):
 """Read bytes from the buffer and advance the read position. Returns the bytes in a bytestring. Parameters size: int, optional Maximum number of bytes to read. If negative or not supplied, read all unread bytes in the buffer. Returns ------- bytes """

        part = self.peek(size)
        self._pos += len(part)
        return part