Created utilities to (down)load datasets and added custom exceptions.

[RicardoJSandoval]

Hi! In this pull request I'm adding the following files:

• exceptions.py: contains custom exceptions.
• utils/load_utils.py: contains a utility function that helps us extract the contents from a zip file.
• utils/download_utils.py: contains utility functions that help us download files from specified URLs (I've also added the ability to do this asynchronously using the concurrent.futures library) and help us figure out which files need to be downloaded.
• utils/files_resources.py: contains a dataclass that stores information needed to (down)load a dataset.
• utils/__init__.py: to make the utils directory a module.

This is the first pull request from the series of pull requests I specified here.

[mrtzh]

LGTM - would you be able to add some tests for the file path and download logic? Thanks!

[RicardoJSandoval]

LGTM - would you be able to add some tests for the file path and download logic? Thanks!

Just pushed a set of tests! Note in order to be able to make mock requests in the tests, I'm using the requests-mock package (linked here). Therefore, we'll have to update the requirements.txt file. I'll go ahead add another pull request for this.

I also added a new exception (InvalidFilePath) and improved the load_utils.extract_content_from_zip function.

[ludwigschmidt]

Looks good! I really like that we're using pathlib everywhere. I left a few comments. Also please make sure the tests pass before we merge the PR. The requests-mock dependency may have to go into tests_require of setup.py instead of requirements.txt.

[RicardoJSandoval]

Hi Ludwig! Thanks for all the comments/observations. I'll go ahead and answer each of them individually. I'll also make sure to add the requests-mock dependency to test_require in setup.py and remove it from requirements.txt.

[ludwigschmidt]

Great thank you! Let me know when I should re-run the tests in case you can't do that yet (I think there may be some restrictions on first-time committers). I just re-ran them and they didn't succeed yet.

[RicardoJSandoval]

I'll push some new code. It seems like the requests-mock package wasn't installed before running the integration tests, so I just added a line to the GitHub workflow to, hopefully, solve this issue.

[mrtzh]

Thanks for all the work! Merging now.