ModuleNotFoundError: No module named 'babble'

[SkySailing]

after follow the code in chapter 2:Embedding more complicated apps.
get the output

Traceback (most recent call last):
  File "/Users/zhangsan/opt/miniconda3/lib/python3.9/runpy.py", line 197, in _run_module_as_main
    return _run_code(code, main_globals, None,
  File "/Users/zhangsan/opt/miniconda3/lib/python3.9/runpy.py", line 87, in _run_code
    exec(code, run_globals)
  File "/Users/zhangsan/.pex/unzipped_pexes/91dc0383d414a80b949b8e4b1404a3ea7be966ad/__main__.py", line 103, in <module>
    bootstrap_pex(__entry_point__, execute=__execute__, venv_dir=__venv_dir__)
  File "/Users/zhangsan/.pex/unzipped_pexes/91dc0383d414a80b949b8e4b1404a3ea7be966ad/.bootstrap/pex/pex_bootstrapper.py", line 601, in bootstrap_pex
    pex.PEX(entry_point).execute()
  File "/Users/zhangsan/.pex/unzipped_pexes/91dc0383d414a80b949b8e4b1404a3ea7be966ad/.bootstrap/pex/pex.py", line 540, in execute
    sys.exit(self._wrap_coverage(self._wrap_profiling, self._execute))
  File "/Users/zhangsan/.pex/unzipped_pexes/91dc0383d414a80b949b8e4b1404a3ea7be966ad/.bootstrap/pex/pex.py", line 447, in _wrap_coverage
    return runner(*args)
  File "/Users/zhangsan/.pex/unzipped_pexes/91dc0383d414a80b949b8e4b1404a3ea7be966ad/.bootstrap/pex/pex.py", line 478, in _wrap_profiling
    return runner(*args)
  File "/Users/zhangsan/.pex/unzipped_pexes/91dc0383d414a80b949b8e4b1404a3ea7be966ad/.bootstrap/pex/pex.py", line 567, in _execute
    return self.execute_entry(
  File "/Users/zhangsan/.pex/unzipped_pexes/91dc0383d414a80b949b8e4b1404a3ea7be966ad/.bootstrap/pex/pex.py", line 749, in execute_entry
    return self.execute_entry_point(entry_point)
  File "/Users/zhangsan/.pex/unzipped_pexes/91dc0383d414a80b949b8e4b1404a3ea7be966ad/.bootstrap/pex/pex.py", line 766, in execute_entry_point
    runner = entry_point.resolve()
  File "/Users/zhangsan/.pex/unzipped_pexes/91dc0383d414a80b949b8e4b1404a3ea7be966ad/.bootstrap/pex/dist_metadata.py", line 724, in resolve
    module = importlib.import_module(self.module)
  File "/Users/zhangsan/opt/miniconda3/lib/python3.9/importlib/__init__.py", line 127, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1030, in _gcd_import
  File "<frozen importlib._bootstrap>", line 1007, in _find_and_load
  File "<frozen importlib._bootstrap>", line 984, in _find_and_load_unlocked
ModuleNotFoundError: No module named 'babble'

[h4110w33n]

The error indicates pex builder can't address the babble module. Let's check to see if it is installed right. From that same section, it would be the following command:

python setup.py develop

If you've ran that already and you hit the same error when trying to compile, then we should check these two things next:

1. Could you run pip freeze or pip list to see if the babble module is installed?
2. If babble (version 0.1) is installed, could you enter into an interactive Python shell and try to import it? As in: import babble

[SkySailing]

i fix this bug by this, build the pex file by following code.

pex -r requirements.txt  -f . babble --disable-cache  -o babble.pex -e babble:launcher

-f . babble to find the package from the current path.