rosdep equivalent of pip freeze and pip install requirements.txt

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Does rosdep have a way to save requirements to a flat file (possibly with frozen versions) and then install from that file later? I'm creating my ROS environment within Docker, and having such a file is nice because it's easy to repeatably build images, and creates a full dependency list that is easily inspected and version controlled. If not, there are other ways to build the image, but I figured I'd ask first.