Compatibility with Python 3.7

[nateraw]

So related to #56 , Colab's environment uses Python 3.7. Since in the package you are using typing.Final, it makes this package unusable on Python 3.7 unfortunately, as that is only supported on Python >= 3.8

Would it be possible to not use this typing feature so the package works on Python < 3.8?

[nateraw]

This issue can be worked around rather easily by adding calls to import from typing_extensions if the version is less than 3.8.

import sys

if sys.version_info < (3, 8):
    from typing_extensions import Final
else:
    from typing import Final

[cragwolfe]

Thanks for the tip @nateraw , we will look into adding 3.7 support.

[firmai]

You might be happy to hear the Colab has recently updated to 3.8. I still run 3.7 environments, and stumbled across the following problem

This should be changed:

if sys.version_info < (3, 8):
    from typing_extensions import Final, List, Optional
else:
    from typing import Final, List, Optional

To this:

from typing import  List, Optional
if sys.version_info < (3, 8):
    from typing_extensions import Final
else:
    from typing import Final

https://github.com/Unstructured-IO/unstructured/blob/main/unstructured/partition/text_type.py

ImportError: cannot import name 'List' from 'typing_extensions' (/opt/conda/lib/python3.7/site-packages/typing_extensions.py)

[cragwolfe]

This was completed with #108 .