This was previously Darwin-only but I ran into the same situation when
building finance/gnucash on NetBSD. /usr/pkg/bin/python happened to be
2.7, but it was used instead of python3.7, leading to a build failure.
This commit fixes that.
Python 3.7.0 is the newest major release of the Python language, and it contains many new features and optimizations.
Among the major new features in Python 3.7 are:
PEP 539, new C API for thread-local storage
PEP 545, Python documentation translations
New documentation translations: Japanese, French, and Korean.
PEP 552, Deterministic pyc files
PEP 553, Built-in breakpoint()
PEP 557, Data Classes
PEP 560, Core support for typing module and generic types
PEP 562, Customization of access to module attributes
PEP 563, Postponed evaluation of annotations
PEP 564, Time functions with nanosecond resolution
PEP 565, Improved DeprecationWarning handling
PEP 567, Context Variables
Avoiding the use of ASCII as a default text encoding (PEP 538, legacy C locale coercion and PEP 540, forced UTF-8 runtime mode)
The insertion-order preservation nature of dict objects is now an official part of the Python language spec.
Notable performance improvements in many areas.
setuptools is one of the basic methods to install python packages.
However, since 34.0 it does not provide its dependencies any longer;
so they need to be installed from pkgsrc.
For bootstrapping, python itself comes with a copy of (pip and) setuptools.
Use this copy to install the necessary packages. They need to be
marked by BOOTSTRAP_SETUPTOOLS=yes for this.
Summary – Release highlights
New syntax features:
PEP 498, formatted string literals.
PEP 515, underscores in numeric literals.
PEP 526, syntax for variable annotations.
PEP 525, asynchronous generators.
PEP 530: asynchronous comprehensions.
New library modules:
secrets: PEP 506 – Adding A Secrets Module To The Standard Library.
CPython implementation improvements:
The dict type has been reimplemented to use a more compact representation based on a proposal by Raymond Hettinger and similar to the PyPy dict implementation. This resulted in dictionaries using 20% to 25% less memory when compared to Python 3.5.
Customization of class creation has been simplified with the new protocol.
The class attribute definition order is now preserved.
The order of elements in **kwargs now corresponds to the order in which keyword arguments were passed to the function.
DTrace and SystemTap probing support has been added.
The new PYTHONMALLOC environment variable can now be used to debug the interpreter memory allocation and access errors.
Significant improvements in the standard library:
The asyncio module has received new features, significant usability and performance improvements, and a fair amount of bug fixes. Starting with Python 3.6 the asyncio module is no longer provisional and its API is considered stable.
A new file system path protocol has been implemented to support path-like objects. All standard library functions operating on paths have been updated to work with the new protocol.
The datetime module has gained support for Local Time Disambiguation.
The typing module received a number of improvements and is no longer provisional.
The tracemalloc module has been significantly reworked and is now used to provide better output for ResourceWarning as well as provide better diagnostics for memory allocation errors. See the PYTHONMALLOC section for more information.
Security improvements:
The new secrets module has been added to simplify the generation of cryptographically strong pseudo-random numbers suitable for managing secrets such as account authentication, tokens, and similar.
On Linux, os.urandom() now blocks until the system urandom entropy pool is initialized to increase the security. See the PEP 524 for the rationale.
The hashlib and ssl modules now support OpenSSL 1.1.0.
The default settings and feature set of the ssl module have been improved.
The hashlib module received support for the BLAKE2, SHA-3 and SHAKE hash algorithms and the scrypt() key derivation function.
This will set all normal files to NONBINMODE (=644) avoiding, in the first
place, install warnings and errors about world and/or group writeability.
Some modules may even be shipped with egg-info files having mode 600
which has an adverse side-effect of wreaking havoc with setuptools
find_package() for *any* python module after installation of the culprit.
Ensuring world and group readability fixes this anomaly.
ok'd by wiz@
New syntax features:
* PEP 492, coroutines with async and await syntax.
* PEP 465, a new matrix multiplication operator: a @ b.
* PEP 448, additional unpacking generalizations.
New library modules:
* typing: PEP 484 – Type Hints.
* zipapp: PEP 441 Improving Python ZIP Application Support.
New built-in features:
* bytes % args, bytearray % args: PEP 461 – Adding % formatting to bytes and bytearray.
* New bytes.hex(), bytearray.hex() and memoryview.hex() methods. (Contributed by Arnon Yaari in issue 9951.)
* memoryview now supports tuple indexing (including multi-dimensional). (Contributed by Antoine Pitrou in issue 23632.)
* Generators have a new gi_yieldfrom attribute, which returns the object being iterated by yield from expressions. (Contributed by Benno Leslie and Yury Selivanov in issue 24450.)
* A new RecursionError exception is now raised when maximum recursion depth is reached. (Contributed by Georg Brandl in issue 19235.)
CPython implementation improvements:
* When the LC_TYPE locale is the POSIX locale (C locale), sys.stdin and sys.stdout now use the surrogateescape error handler, instead of the strict error handler. (Contributed by Victor Stinner in issue 19977.)
* .pyo files are no longer used and have been replaced by a more flexible scheme that includes the optimization level explicitly in .pyc name. (See PEP 488 overview.)
* Builtin and extension modules are now initialized in a multi-phase process, which is similar to how Python modules are loaded. (See PEP 489 overview.)
Significant improvements in the standard library:
* collections.OrderedDict is now implemented in C, which makes it 4 to 100 times faster.
* The ssl module gained support for Memory BIO, which decouples SSL protocol handling from network IO.
* The new os.scandir() function provides a better and significantly faster way of directory traversal.
* functools.lru_cache() has been mostly reimplemented in C, yielding much better performance.
* The new subprocess.run() function provides a streamlined way to run subprocesses.
* The traceback module has been significantly enhanced for improved performance and developer convenience.
Security improvements:
* SSLv3 is now disabled throughout the standard library. It can still be enabled by instantiating a ssl.SSLContext manually. (See issue 22638 for more details; this change was backported to CPython 3.4 and 2.7.)
* HTTP cookie parsing is now stricter, in order to protect against potential injection attacks. (Contributed by Antoine Pitrou in issue 22796.)
Windows improvements:
* A new installer for Windows has replaced the old MSI. See Using Python on Windows for more information.
* Windows builds now use Microsoft Visual C++ 14.0, and extension modules should use the same.
