As support for Python 3.5 and lower was dropped, we can use more modern syntax

As support for Python 3.5 and lower was dropped, we can use more modern syntax

As support for Python 3.5 and lower was dropped, we can use more modern syntax

As support for Python 3.5 and lower was dropped, we can use more modern syntax

The 2.0.0 release of PyPDF2 includes three core changes:

1. Dropping support for Python 3.5 and older.
2. Introducing type annotations.
3. Interface changes, mostly to have PEP8-compliant names

We introduced a [deprecation process](#930)
that hopefully helps users to avoid unexpected breaking changes.

Breaking Changes(DEP):
- PyPDF2 2.0 requires Python 3.6+. Python 2.7 and 3.5 support were dropped.
- PdfFileReader: The "warndest" parameter was removed
- PdfFileReader and PdfFileMerger no longer have the `overwriteWarnings`
  parameter. The new behavior is `overwriteWarnings=False`.
- merger: OutlinesObject was removed without replacement.
- merger.py ➔ _merger.py: You must import PdfFileMerger from PyPDF2 directly.
- utils:
  * `ConvertFunctionsToVirtualList` was removed
  * `formatWarning` was removed
  * `isInt(obj)`: Use `instance(obj, int)` instead
  * `u_(s)`: Use `s` directly
  * `chr_(c)`: Use `chr(c)` instead
  * `barray(b)`: Use `bytearray(b)` instead
  * `isBytes(b)`: Use `instance(b, type(bytes()))` instead
  * `xrange_fn`: Use `range` instead
  * `string_type`: Use `str` instead
  * `isString(s)`: Use `instance(s, str)` instead
  * `_basestring`: Use `str` instead
  * All Exceptions are now in `PyPDF2.errors`:
    - PageSizeNotDefinedError
    - PdfReadError
    - PdfReadWarning
    - PyPdfError
- `PyPDF2.pdf` (the `pdf` module) no longer exists. The contents were moved with
  the library. You should most likely import directly from `PyPDF2` instead.
  The `RectangleObject` is in `PyPDF2.generic`.
- The `Resources`, `Scripts`, and `Tests` will no longer be part of the distribution
  files on PyPI. This should have little to no impact on most people. The
  `Tests` are renamed to `tests`, the `Resources` are renamed to `resources`.
  Both are still in the git repository. The `Scripts` are now in
  https://github.com/py-pdf/cpdf. `Sample_Code` was moved to the `docs`.

For a full list of deprecated functions, please see the changelog of version
1.28.0.

New Features (ENH):
-  Improve space setting for text extraction (#922)
-  Allow setting the decryption password in PdfReader.__init__ (#920)
-  Add Page.add_transformation (#883)

Bug Fixes (BUG):
-  Fix error adding transformation to page without /Contents (#908)

Robustness (ROB):
-  Cope with invalid length in streams (#861)

Documentation (DOC):
-  Fix style of 1.25 and 1.27 patch notes (#927)
-  Transformation (#907)

Developer Experience (DEV):
-  Create flake8 config file (#916)
-  Use relative imports (#875)

Maintenance (MAINT):
-  Use Python 3.6 language features (#849)
-  Add wrapper function for PendingDeprecationWarnings (#928)
-  Use new PEP8 compliant names (#884)
-  Explicitly represent transformation matrix (#878)
-  Inline PAGE_RANGE_HELP string (#874)
-  Remove unnecessary generics imports (#873)
-  Remove star imports (#865)
-  merger.py ➔ _merger.py (#864)
-  Type annotations for all functions/methods (#854)
-  Add initial type support with mypy (#853)

Testing (TST):
-  Regression test for xmp_metadata converter (#923)
-  Checkout submodule sample-files for benchmark
-  Add text extracting performance benchmark
-  Use new PyPDF2 API in benchmark (#902)
-  Make test suite fail for uncaught warnings (#892)
-  Remove -OO testrun from CI (#901)
-  Improve tests for convert_to_int (#899)

Full Changelog: 1.28.4...2.0.0