ImportError when running catkin_make_isolated

edit

I'm following the source installation on Debian Stretch on an armel platform. When I come to the final step of running catkin_make_isolated, I get the following error:

$ ./src/catkin/bin/catkin_make_isolated --install -DCMAKE_BUILD_TYPE=Release
Traceback (most recent call last):
  File "./src/catkin/bin/catkin_make_isolated", line 12, in <module>
    from catkin.builder import build_workspace_isolated
  File "./src/catkin/bin/../python/catkin/builder.py", line 66, in <module>
    from catkin_pkg.terminal_color import ansi, disable_ANSI_colors, fmt, sanitize
ImportError: No module named terminal_color

It seems this is due to a version mismatch, but I'm not sure where exactly. I'm running this in a Docker file, so it should be very reproducible:

FROM ev3dev/ev3dev-stretch-ev3-generic

RUN echo "robot ALL=(ALL) NOPASSWD: ALL" >> /etc/sudoers

RUN apt-get install --yes --no-install-recommends python-rosdep python-rosinstall-generator python-wstool python-rosinstall build-essential 

RUN rosdep init
USER robot
RUN rosdep update

RUN mkdir /home/robot/ros_catkin_ws
WORKDIR /home/robot/ros_catkin_ws

RUN rosinstall_generator robot --rosdistro melodic --deps --exclude roslisp --tar > melodic-robot.rosinstall
RUN wstool init -j8 src melodic-robot.rosinstall

RUN rosdep install --os=debian:stretch --from-paths src --ignore-src --rosdistro melodic -y

RUN ./src/catkin/bin/catkin_make_isolated --install -DCMAKE_BUILD_TYPE=Release