title: how does logging_mixin in airflow source code work?
body: <p>I was trying to practice reading source code, so I was reading airflow's source code. </p>
  
  <p>Can somebody explain how logging_mixin.py (<a href="https://github.com/apache/incubator-airflow/blob/master/airflow/utils/log/logging_mixin.py" rel="nofollow noreferrer">github location</a>) works? I tried to use the module with my own class like this: </p>
  
  <pre><code>class Node(LoggingMixin):
  """Linked list node."""
  
  ...
  
  def remove(self):
      self.log.info('remvoed')
  </code></pre>
  
  <p>But when I call remove on a node instance, nothing gets printed out.</p>