Uproot

kkothari2001 implemented `uproot.dask` (for `library="np"` only), a new function to provide Uproot data as Dask arrays: PRs 578, 603. Added another new function, `uproot.num_entries`, for getting the number of TTree entries from a set of files with minimal reading: PR 609.

jpivarski removed tests that rely on a ROOT TStreamerInfo behavior: PR 612. Changed `awkward_form` arguments to `(self, file, context)` so that new pseudo-arguments can be passed through the `context` without another major code change: PR 611. This is to prepare for aryan26roy's AwkwardForth implementation of `AsObjects` interpretations (see 610, WIP targeting Uproot 5).

**Note:** this is the last Uproot 4 release before the repo branches into `main` (for version 5) and `main-v4` (for bug-fixes in Uproot 4, starting with 4.3.0). Uproot 5 will incorporate Awkward version 2, as described in the [Awkward road map](https://github.com/scikit-hep/awkward/wiki#grand-view-and-history), but it will have minimal interface changes relative to Uproot 4 (mostly just `uproot.lazy` → `uproot.dask`).

jpivarski fixed the use of Unicode names for objects in ROOT files: PR 577. Made `flow=True` mean the same thing for Uproot histograms as hist: PR 582. Added an interpretation for `ROOT::VecOps::RVec`: PR 593. Replaced an error message in HTTPSource with a fallback to the non-multipart-GET case: PR 594. Put an upper limit on the time KeyInFileError takes to print itself: PR 595.

jpivarski fixed 572: PR 573.

henryiii removed `wheel` from pyproject.toml: PR 565.

jpivarski added a rule to skip parsing Float16/Double32 TBranch titles if the title is not parsable (and just assume default number of bits): PR 561. Removed references to deprecated `distutils` and Pandas `Int64Index`: PR 564. Removed the rule that interpreted `fBits` as 1 byte (it's 4 bytes everywhere except in some branches of some Delphes files): PR 570.

**Dropped support for Pythons 2.7 and 3.5:** PR 525. From now on, Uproot only supports Python 3.6 and up.

henryiii dropped Python2isms from the codebase: PR 526.

jrueb made writing to Python file handles work (fixed a half-finished, forgotten implementation): PR 538.

jpivarski fixed `cut` jagged-array corner-case in `library="pd"`. Fixed a case in which the instance version is 0, but the streamer version is not: PR 537. Fixed `uproot.WritableTTree.extend` when the metadata needs to be rewritten: PR 547. When checking to see if `something` in `file["name"] = something` is an Awkward Array or Pandas DataFrame for creating a TTree, also check for superclasses (the whole mro): PR 557.

**The 4.1.x series is the last to support Python 2.7 and Python 3.5. From 4.2.0 onward, only Python 3.6 and above will be supported.**

(Any bug-fixes that absolutely must be used in an old Python environment will need to be versions 4.1.10, 4.1.11, etc., and these won't include features and regular maintenance that go into the main branch, 4.2.x and beyond.)

In this version:

pfackeldey removed an unnecessary copy of memory-mapped data.

veprbl exposed the `data` property of TTable: PR 506.

jpivarski added an example of RNTuple header parsing: accidentally as 4bb0f6aedbe7e9a8ba8feb166a16e71274259d26, rather than a formal PR. Added more careful DataFrame-checking code in TTree-writing, to avoid a spurious error message: PR 517. Fixed a picking issue with histograms (just the TAxis) by ensuring that all Behaviors are not Python Abstract Base Classes: PR 521.