Patch by Serhiy Storchaka.

2) _mpd_qpow_mpd(): Abort the loop for all specials, not only infinity.

3) _mpd_qpow_mpd(): Make the function more general and distinguish between
   zero clamping and folding down the exponent. The latter case is currently
   handled by setting context->clamp to 0 before calling the function.

4) _mpd_qpow_int(): Add one to the work precision in case of a negative
   exponent. This is to get the same relative error (0.1 * 10**-prec)
   for both positive and negative exponents. The previous relative
   error for negative exponents was (0.2 * 10**-prec).

   Both errors are _before_ the final rounding to the context precision.

And don't use assert() anymore if check_maxchar is set: return -1 on error
instead.

Py_UCS4 buffer

or datetime objects.

module name into consideration when determining whether a module is a
package or not. This prevents importing a module's __init__ module
directly and having it considered a package, which can lead to
duplicate sub-modules.

Thanks to Ronan Lamy for reporting the bug.

that they are deprecated (previous commit documented this fact in the
module docs).

iter_modules() requires iter_modules() be defined on an importer. The
importers in importlib do not define this non-standard method.

Patch by Serhiy Storchaka.

before resorting to terminate()

Issue #15061: Don't oversell the capabilities of the new non-shortcircuiting comparison function in hmac

Skip XincludeTest entirely instead of just ignoring failures, because it may segfault, depending on the order of running tests

Removed _SimpleElementPath and its flaky test. The test monkey-patches the module, which causes other failures and fails itself depending on the order tests are run.

Replace the iter/itertext methods of Element in _elementtree with true C implementations, instead of the bootstrapped Python code. In addition to being cleaner (removing the last remains of the bootstrapping code in _elementtree), this gives a 10x performance boost for iter() on large documents.
Also reorganized the tests a bit to be more robust.