title: How to write custom python logging handler?
body: <p>How to write custom console log function to output only on the console window log messages on a single line (not append) until the first regular log record.</p>
  
  <pre><code>progress = ProgressConsoleHandler()
  console  = logging.StreamHandler()  
  
  logger = logging.getLogger('test')
  logger.setLevel(logging.DEBUG) 
  logger.addHandler(console)  
  logger.addHandler(progress)
  
  logger.info('test1')
  for i in range(3):
      logger.progress('remaining %d seconds' % i)
      time.sleep(1)   
  logger.info('test2')
  </code></pre>
  
  <p>So that the console output is only three lines:</p>
  
  <pre><code>INFO: test1
  remaining 0 seconds... 
  INFO: test2
  </code></pre>
  
  <p>Any suggestions on the best way on how to implement this?</p>