Pypdf

Bug Fixes (BUG)
- Accept hierarchical fields (1529)

Documentation (DOC)
- Use google style docstrings (1534)
- Fix linked markdown documents (1537)

Developer Experience (DEV)
- Update docs config (1535)

Performance Improvement (PI)
- Help the specializing adaptive interpreter (1522)

New Features (ENH)
- Add support for page labels (1519)

Bug Fixes (BUG)
- upgrade clone_document_root (1520)


[Full Changelog](https://github.com/py-pdf/pypdf/compare/3.1.0...3.1.1)

Move PyPDF2 to pypdf (1513). This now it's all lowercase, no number in the
name. For installation and for import. PyPDF2 will no longer receive updates.
The community should move back to its roots.

If you were still using pyPdf or PyPDF2 < 2.0.0, I recommend reading the
migration guide: https://pypdf.readthedocs.io/en/latest/user/migration-1-to-2.html

pypdf==3.1.0 is only different from PyPDF2==3.0.0 in the package name.
Replacing "PyPDF2" by "pypdf" should be enough if you migrate from
`PyPDF2==3.0.0` to `pypdf==3.1.0`.

[Full Changelog](https://github.com/py-pdf/pypdf/compare/3.0.0...3.1.0)

BREAKING CHANGES ⚠️
- Deprecate features with PyPDF2==3.0.0 (1489)
- Refactor Fit / Zoom parameters (1437)

New Features (ENH)
- Add Cloning (1371)
- Allow int for indirect_reference in PdfWriter.get_object (1490)

Documentation (DOC)
- How to read PDFs from S3 (1509)
- Make MyST parse all links as simple hyperlinks (1506)
- Changed 'latest' for 'stable' generated docs (1495)
- Adjust deprecation procedure (1487)

Maintenance (MAINT)
- Use typing.IO for file streams (1498)


[Full Changelog](https://github.com/py-pdf/PyPDF2/compare/2.12.1...3.0.0)

Documentation (DOC)
- Deduplicate extract_text docstring (1485)
- How to cite PyPDF2 (1476)

Maintenance (MAINT)
Consistency changes:
- indirect_ref/ido ➔ indirect_reference, dest➔ page_destination (1467)
- owner_pwd/user_pwd ➔ owner_password/user_password (1483)
- position ➜ page_number in Merger.merge (1482)
- indirect_ref ➜ indirect_reference (1484)

[Full Changelog](https://github.com/py-pdf/PyPDF2/compare/2.12.0...2.12.1)

New Features (ENH)
- Add support to extract gray scale images (1460)
- Add 'threads' property to PdfWriter (1458)
- Add 'open_destination' property to PdfWriter (1431)
- Make PdfReader.get_object accept integer arguments (1459)

Bug Fixes (BUG)
- Scale PDF annotations (1479)

Robustness (ROB)
- Padding issue with AES encryption (1469)
- Accept empty object as null objects (1477)

Documentation (DOC)
- Add module documentation the PaperSize class (1447)

Maintenance (MAINT)
- Use 'page_number' instead of 'pagenum' (1365)
- Add List of pages to PageRangeSpec (1456)

Testing (TST)
- Cleanup temporary files (1454)
- Mark test_tounicode_is_identity as external (1449)
- Use Ubuntu 20.04 for running CI test suite (1452)

[Full Changelog](https://github.com/py-pdf/PyPDF2/compare/2.11.2...2.12.0)