When building the [opensearch charm](https://github.com/canonical/opensearch-operator) on charmcraft 2.3, it now fails to parse a file named [helper_charm.py](https://github.com/canonical/opensearch-operator/blob/main/lib/charms/opensearch/v0/helper_charm.py). Here's the interesting part of the stacktrace: ``` 2023-05-10 15:09:31.249 :: 2023-05-10 14:09:30.900 Packing the charm. 2023-05-10 15:09:31.249 :: 2023-05-10 14:09:30.900 Reading '/root/project/metadata.yaml' 2023-05-10 15:09:31.249 :: 2023-05-10 14:09:30.903 Validating metadata format 2023-05-10 15:09:31.249 :: 2023-05-10 14:09:30.909 Building for 'bases[0]' as host matches 'build-on[0]'. 2023-05-10 15:09:31.249 :: 2023-05-10 14:09:30.909 Building for 'bases[0][0]'. 2023-05-10 15:09:31.249 :: 2023-05-10 14:09:30.909 Building charm in '/root' 2023-05-10 15:09:31.249 :: 2023-05-10 14:09:30.926 Failed to parse Python library 'lib/charms/opensearch/v0/helper_charm.py' 2023-05-10 15:09:40.008 Failed to build charm for bases index '0'. 2023-05-10 15:09:40.011 Traceback (most recent call last): 2023-05-10 15:09:40.011 File "/snap/charmcraft/1349/lib/charmcraft/commands/build.py", line 388, in pack_charm_in_instance 2023-05-10 15:09:40.011 instance.execute_run(cmd, check=True, cwd=instance_output_dir) 2023-05-10 15:09:40.011 File "/snap/charmcraft/1349/lib/craft_providers/lxd/lxd_instance.py", line 289, in execute_run 2023-05-10 15:09:40.011 return self.lxc.exec( 2023-05-10 15:09:40.011 File "/snap/charmcraft/1349/lib/craft_providers/lxd/lxc.py", line 371, in exec 2023-05-10 15:09:40.011 return runner(final_cmd, **kwargs) # pylint: disable=subprocess-run-check 2023-05-10 15:09:40.011 File "/snap/charmcraft/1349/usr/lib/python3.8/subprocess.py", line 516, in run 2023-05-10 15:09:40.011 raise CalledProcessError(retcode, process.args, 2023-05-10 15:09:40.011 subprocess.CalledProcessError: Command '['lxc', '--project', 'charmcraft', 'exec', 'local:charmcraft-opensearch-35655756-0-0-amd64', '--cwd', '/root/project', '--', 'env', 'PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/snap/bin', 'CHARMCRAFT_MANAGED_MODE=1', 'charmcraft', 'pack', '--bases-index', '0', '--verbosity=brief']' returned non-zero exit status 1. ``` To reproduce, just build the `main` branch of the [opensearch charm](https://github.com/canonical/opensearch-operator) with charmcraft v2.3.