title: Airflow - Push xcom from SparkSubmitOperator
body: <p>I need to push a value obtained inside of a spark job which is written in python.
  After this I will use that value to feed a Branch Operator and decide which path to take in the job flow.</p>
  <p>So far, I have been trying to extend the SparkSubmitOperator to allow that, but with no success.
  I've found <a href="https://stackoverflow.com/questions/56529331/airflow-sparksubmitoperator-push-value-to-xcom">this</a> and <a href="https://stackoverflow.com/questions/65247784/is-airflow-xcom-job-isolated?rq=1">this</a>, but none of those solutions seem to work for me, although they helped me understand a bit more how I might approach the problem.</p>
  <p>Is it possible to modify de SparkSubmitOperator in a way I can use xcom_push from the python file running inside of it?</p>