(rml_venv_bionic) dsun@dsun-voyager:~/Dropbox/Programs/git_repos/pebl_bionic$ pip install em
Collecting em
  Downloading em-0.4.0.tar.gz (10 kB)
Building wheels for collected packages: em
  Building wheel for em (setup.py) ... done
  Created wheel for em: filename=em-0.4.0-py3-none-any.whl size=13021 sha256=845d869731a28abb353da1c528b09cd9f7df4ac996bb91ab2a62a306cf00d599
  Stored in directory: /home/dsun/.cache/pip/wheels/3e/c2/ea/528c42e485ccf40cb18a105cbdf02bc9f7f0bd37e764769f17
Successfully built em
Installing collected packages: em
Successfully installed em-0.4.0
(rml_venv_bionic) dsun@dsun-voyager:~/Dropbox/Programs/git_repos/pebl_bionic$ colcon build
Starting >>> romela_peble
--- stderr: romela_peble
CMake Error at /opt/ros/eloquent/share/rosidl_adapter/cmake/rosidl_adapt_interfaces.cmake:60 (message):
  execute_process(/home/dsun/.virtualenvs/rml_venv_bionic/bin/python3 -m
  rosidl_adapter --package-name romela_peble --arguments-file
  /home/dsun/Dropbox/Programs/git_repos/pebl_bionic/build/romela_peble/rosidl_adapter__arguments__romela_peble.json
  --output-dir
  /home/dsun/Dropbox/Programs/git_repos/pebl_bionic/build/romela_peble/rosidl_adapter/romela_peble
  --output-file
  /home/dsun/Dropbox/Programs/git_repos/pebl_bionic/build/romela_peble/rosidl_adapter/romela_peble.idls)
  returned error code 1:

  AttributeError processing template 'msg.idl.em'

  Traceback (most recent call last):

    File "/opt/ros/eloquent/lib/python3.6/site-packages/rosidl_adapter/resource/__init__.py", line 48, in evaluate_template
      _interpreter = em.Interpreter(

  AttributeError: module 'em' has no attribute 'Interpreter'



  During handling of the above exception, another exception occurred:



  Traceback (most recent call last):

    File "/usr/lib/python3.6/runpy.py", line 193, in _run_module_as_main
      "__main__", mod_spec)
    File "/usr/lib/python3.6/runpy.py", line 85, in _run_code
      exec(code, run_globals)
    File "/opt/ros/eloquent/lib/python3.6/site-packages/rosidl_adapter/__main__.py", line 19, in <module>
      sys.exit(main())
    File "/opt/ros/eloquent/lib/python3.6/site-packages/rosidl_adapter/main.py", line 55, in main
      pathlib.Path(relative_path), output_dir)
    File "/opt/ros/eloquent/lib/python3.6/site-packages/rosidl_adapter/__init__.py", line 20, in convert_to_idl
      package_dir, package_name, interface_file, output_dir / 'msg')
    File "/opt/ros/eloquent/lib/python3.6/site-packages/rosidl_adapter/msg/__init__.py", line 39, in convert_msg_to_idl
      expand_template('msg.idl.em', data, output_file, encoding='iso-8859-1')
    File "/opt/ros/eloquent/lib/python3.6/site-packages/rosidl_adapter/resource/__init__.py", line 23, in expand_template
      content = evaluate_template(template_name, data)
    File "/opt/ros/eloquent/lib/python3.6/site-packages/rosidl_adapter/resource/__init__.py", line 69, in evaluate_template
      _interpreter.shutdown()

  AttributeError: 'NoneType' object has no attribute 'shutdown'

Call Stack (most recent call first):
  /opt/ros/eloquent/share/rosidl_cmake/cmake/rosidl_generate_interfaces.cmake:130 (rosidl_adapt_interfaces)
  CMakeLists.txt:45 (rosidl_generate_interfaces)


---
Failed   <<< romela_peble	[ Exited with code 1 ]

Summary: 0 packages finished [0.74s]
  1 package failed: romela_peble
  1 package had stderr output: romela_peble