feat/improved json

[corneliusroemer]

• Automatic data update
• Produce empty lists and new aa_nuc_mappings

Description of proposed changes

What is the goal of this pull request? What does this pull request change?

Related issue(s)

Fixes #
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Testing

What steps should be taken to test the changes you've proposed?
If you added or changed behavior in the codebase, did you update the tests, or do you need help with this?

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