ROS 2 custom message build error "abc" package

edit

Hello,

I am testing creation of custom message packages in ROS 2 with colcon tools.
I have 2 test packages:

1. abc/MyMsg.msg - custom message package named "abc" that contains a message "MyMsg.msg"
2. use_abc_msg/UseMyMsg.msg - custom message package named "use_abc_msgs" contains a message "UseMyMsg.msg" that refers to "abc/MyMsg".

I get strange python errors when building this simple hierarchy of custom message packages. Errors are shown below:

Starting >>> abc
[Processing: abc]
Finished <<< abc [38.7s]
Starting >>> use_abc_msgs
--- stderr: use_abc_msgs
Fatal Python error: init_sys_streams: can't initialize sys standard streams
Traceback (most recent call last):
  File "C:\Python37\lib\io.py", line 72, in <module>
**AttributeError: module 'abc' has no attribute 'ABCMeta'**
CMake Error at C:/dev/ros2/share/ament_cmake_core/cmake/ament_cmake_package_templates-extras.cmake:41 (message):
  execute_process(C:/Python37/python.exe
  C:/dev/ros2/share/ament_cmake_core/cmake/package_templates/templates_2_cmake.py
  C:/test/build/use_abc_msgs/ament_cmake_package_templates/templates.cmake)
  **returned error code Exit code 0xc0000409**

Call Stack (most recent call first):
  C:/dev/ros2/share/ament_cmake_core/cmake/ament_cmake_coreConfig.cmake:38 (include)
  C:/dev/ros2/share/ament_cmake/cmake/ament_cmake_export_dependencies-extras.cmake:15 (find_package)
  C:/dev/ros2/share/ament_cmake/cmake/ament_cmakeConfig.cmake:38 (include)
  CMakeLists.txt:19 (find_package)

I don't understand how Python Abstract Base Classes are invoked.

I found a similar posting related to ROS 1 Catkin, but did not see a satisfactory solution.

System environment

Operating System: Windows 10

ROS 2 version: Dashing (built from sources)

CMake version: 3.14.7

Python version: 3.7.2

I have attached the zip archive test_custom_msg.zip that shows this issue:

Reproduction steps:

1. Extract the zip-archive.
2. Change folder to the extracted archive.
3. Run local_setup.bat or setup.bash for ROS 2 (I'm sure this is platform independent).
4. Run "colcon build --merge-install".

Any guidance will be greatly appreciated.

Thanks.