compatibility with downloading data from gcp

[dangthatsright]

Similar to the S3 data downloading, this works for GCP. I've tested it with my own data but not sure how I would set up tests for this repo.

The link to the contributor guideline is dead btw.

If there are specific places you would like me to update, please let me know.

Before submitting

• Was this discussed/agreed via a Github issue? (no need for typos and docs improvements)
• Did you read the contributor guideline, Pull Request section?
• Did you make sure to update the docs?
• Did you write any new necessary tests?

What does this PR do?

Fixes #94 #101

PR review

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[codecov]

Codecov Report

Attention: Patch coverage is 89.28571% with 3 lines in your changes missing coverage. Please review.

Please upload report for BASE (main@6519a98). Learn more about missing BASE report.

Additional details and impacted files

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[tchaton]

Hey @dangthatsright. I have fixed the failure in the test. When you import an optional package, you need to make sure the logic is protected by a boolean to avoid failures when it is not available.

I wondered if you would be keen on contributing the same feature for the optimize method, so users can generate their data and push directly to gcs.

Something like this:

optimize(
    ....
    output_dir="gcs://....",
) 

Also, feel free to join our discord: https://discord.gg/fVrkqu5g. We have channel called #litdata to talk about the future of the library.