<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def tail(self, bytes):
 """ Returns the number of given bytes from the tail of the buffer. The buffer remains unchanged. :type bytes: int :param bytes: The number of bytes to return. """

        self.io.seek(max(0, self.size() - bytes))
        return self.io.read()