Binarized memmap dataloader for Megatron NMT, Inference and checkpoint -> nemo

[MaximumEntropy]

What does this PR do ?

1. Adds megatron memory-mapped dataloaders to NMT.
2. Inference script/config with a translate() method.

Collection: NLP

Changelog

• Add a new dataset class for megatron memmap dataset.
• Add an inference script with the associated yaml config.
• Change the use_tarred_dataset arg to a generic dataset_type arg that can take [text, tarred, bin_memmap, text_memmap]

Usage

• Set the following in the yaml config

• dataset_type: bin_memmap.

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• New Feature
• Bugfix
• Documentation

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Additional Information

• Related to # (issue)

[lgtm-com]

This pull request fixes 1 alert when merging 590f40e into 470587a - view on LGTM.com

fixed alerts:

• 1 for Unused import

[lgtm-com]

This pull request fixes 1 alert when merging 968938b into 470587a - view on LGTM.com

fixed alerts:

• 1 for Unused import

[lgtm-com]

This pull request introduces 5 alerts and fixes 2 when merging fd0b976 into e838862 - view on LGTM.com

new alerts:

• 2 for Unused import
• 2 for `__init__` method calls overridden method
• 1 for Unused local variable

fixed alerts:

• 1 for Unused import
• 1 for `__init__` method calls overridden method

[lgtm-com]

This pull request introduces 5 alerts and fixes 2 when merging 09884f3 into e838862 - view on LGTM.com

new alerts:

• 2 for Unused import
• 2 for `__init__` method calls overridden method
• 1 for Unused local variable

fixed alerts:

• 1 for Unused import
• 1 for `__init__` method calls overridden method

[lgtm-com]

This pull request introduces 5 alerts and fixes 2 when merging ff3df3d into f6936ce - view on LGTM.com

new alerts:

• 2 for Unused import
• 2 for `__init__` method calls overridden method
• 1 for Unused local variable

fixed alerts:

• 1 for Unused import
• 1 for `__init__` method calls overridden method

[lgtm-com]

This pull request introduces 5 alerts and fixes 2 when merging a6c9dda into f6936ce - view on LGTM.com

new alerts:

• 2 for Unused import
• 2 for `__init__` method calls overridden method
• 1 for Unused local variable

fixed alerts:

• 1 for Unused import
• 1 for `__init__` method calls overridden method

[lgtm-com]

This pull request introduces 5 alerts and fixes 2 when merging 2d3ba1a into 2af3786 - view on LGTM.com

new alerts:

• 2 for Unused import
• 2 for `__init__` method calls overridden method
• 1 for Unused local variable

fixed alerts:

• 1 for Unused import
• 1 for `__init__` method calls overridden method

[lgtm-com]

This pull request introduces 5 alerts and fixes 2 when merging 4214909 into f9d45db - view on LGTM.com

new alerts:

• 2 for Unused import
• 2 for `__init__` method calls overridden method
• 1 for Unused local variable

fixed alerts:

• 1 for Unused import
• 1 for `__init__` method calls overridden method

[lgtm-com]

This pull request introduces 5 alerts and fixes 2 when merging 37cda3b into ed35577 - view on LGTM.com

new alerts:

• 2 for Unused import
• 2 for `__init__` method calls overridden method
• 1 for Unused local variable

fixed alerts:

• 1 for Unused import
• 1 for `__init__` method calls overridden method

[lgtm-com]

This pull request introduces 5 alerts and fixes 2 when merging 86137df into 760e628 - view on LGTM.com

new alerts:

• 2 for Unused import
• 2 for `__init__` method calls overridden method
• 1 for Unused local variable

fixed alerts:

• 1 for Unused import
• 1 for `__init__` method calls overridden method