title: airflow 2 / docker-compose: how to install Python dependencies for DAGs?
body: <p>I have installed airflow 2.0.2 using docker-compose as described under <a href="https://airflow.apache.org/docs/apache-airflow/stable/start/docker.html" rel="nofollow noreferrer">https://airflow.apache.org/docs/apache-airflow/stable/start/docker.html</a>.</p>
  <p>I have researched quite some time, but I don't find a way to install python dependencies for my DAGs. I know how to do this using a Dockerfile (<code>COPY requirements.txt /app</code> / <code>RUN pip install -r requirements.txt</code>), but there is no Dockerfile involved here.</p>
  <ul>
  <li>How to install python dependencies in airflow 2.0.2 / docker-compose?</li>
  <li>On which of the six containers which are deployed when using the custom docker-compose do I need to install the dependencies?</li>
  </ul>