use list() to wrap range() in itertools.permutations() example; thanks to Romain MORLEVAT from docs@

dropped connections in case of simultaneous connection requests.

common_types was mentioned under MimeTypes class, move it to helper function
category and other documentation improvements contributed by Sandro Tosi.

Metaclasses with metaclasses with a __dict__ descriptor can no longer trigger code execution with inspect.getattr_static.
Closes issue 11829.

Issue #13597: Fix the documentation of the "-u" command-line option, and wording of "What's new in Python 3.0" about standard streams.

Also fixes issue #13581: `help(type)` wouldn't display anything.

support multiprocessing.Event.

Patch by Philipp Hagemeister.

failing.

traceback if Python is optimized.

 * delay the lookup of the size_t type, it is not available at startup
 * The second argument of the PyFrameObjectPtr constructor is optional, as
   done in other constructors
 * iter_builtins() and iter_globals() methods of PyFrameObjectPtr returns
   an empty tuple instead of None if Python is optimized
 * Fix py-bt and py-bt-full to handle correctly "optimized" frames
 * Frame.get_pyop() tries to get the frame pointer from PyEval_EvalCodeEx()
   if the pointer is optimized out in PyEval_EvalFrameEx()

race condition).

Closes issue 11813.