Import statements in examples are not working

[rclune]

In the 'Dataset Exploration and Management in AtomWorks' example the first import statement:

from atomworks.ml.datasets.datasets import FileDataset

results in the following error when using AtomWorks installed from PyPI:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/opt/miniconda3/envs/atomworks_env/lib/python3.12/site-packages/atomworks/ml/datasets/datasets.py", line 18, in <module>
    from atomworks.ml.datasets.parsers import MetadataRowParser, load_example_from_metadata_row
  File "/opt/miniconda3/envs/atomworks_env/lib/python3.12/site-packages/atomworks/ml/datasets/parsers/__init__.py", line 3, in <module>
    from atomworks.ml.datasets.parsers.default_metadata_row_parsers import *  # noqa: F403
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/miniconda3/envs/atomworks_env/lib/python3.12/site-packages/atomworks/ml/datasets/parsers/default_metadata_row_parsers.py", line 86, in <module>
    class PNUnitsDFParser(MetadataRowParser):
  File "/opt/miniconda3/envs/atomworks_env/lib/python3.12/site-packages/atomworks/ml/datasets/parsers/default_metadata_row_parsers.py", line 99, in PNUnitsDFParser
    base_dir: Path | str | list[Path | str] | tuple[Path | str, ...] = Path(PDB_MIRROR_PATH),
                                                                       ^^^^^^^^^^^^^^^^^^^^^
  File "/opt/miniconda3/envs/atomworks_env/lib/python3.12/pathlib.py", line 1162, in __init__
    super().__init__(*args)
  File "/opt/miniconda3/envs/atomworks_env/lib/python3.12/pathlib.py", line 373, in __init__
    raise TypeError(
TypeError: argument should be a str or an os.PathLike object where __fspath__ returns a str, not 'NoneType'
>>> from atomworks.ml.datasets.datasets import FileDataset
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/opt/miniconda3/envs/atomworks_env/lib/python3.12/site-packages/atomworks/ml/datasets/datasets.py", line 18, in <module>
    from atomworks.ml.datasets.parsers import MetadataRowParser, load_example_from_metadata_row
  File "/opt/miniconda3/envs/atomworks_env/lib/python3.12/site-packages/atomworks/ml/datasets/parsers/__init__.py", line 3, in <module>
    from atomworks.ml.datasets.parsers.default_metadata_row_parsers import *  # noqa: F403
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/miniconda3/envs/atomworks_env/lib/python3.12/site-packages/atomworks/ml/datasets/parsers/default_metadata_row_parsers.py", line 86, in <module>
    class PNUnitsDFParser(MetadataRowParser):
  File "/opt/miniconda3/envs/atomworks_env/lib/python3.12/site-packages/atomworks/ml/datasets/parsers/default_metadata_row_parsers.py", line 99, in PNUnitsDFParser
    base_dir: Path | str | list[Path | str] | tuple[Path | str, ...] = Path(PDB_MIRROR_PATH),
                                                                       ^^^^^^^^^^^^^^^^^^^^^
  File "/opt/miniconda3/envs/atomworks_env/lib/python3.12/pathlib.py", line 1162, in __init__
    super().__init__(*args)
  File "/opt/miniconda3/envs/atomworks_env/lib/python3.12/pathlib.py", line 373, in __init__
    raise TypeError(
TypeError: argument should be a str or an os.PathLike object where __fspath__ returns a str, not 'NoneType'

This error is not present if using AtomWorks installed locally from source.