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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 end(self, close_fileobj=True):
 """Perform session cleanup, since the end method should always be called explicitely by the calling code, this works better than the destructor. Set close_fileobj to False so fileobj can be returned open."""

        log.debug("in TftpContext.end - closing socket")
        self.sock.close()
        if close_fileobj and self.fileobj is not None and not self.fileobj.closed:
            log.debug("self.fileobj is open - closing")
            self.fileobj.close()