Best day trading platforms broker 201528 comments
Day trading asx software
This article explains the new features in Python 3. For full details, see the changelog. PEP — Python 3. Please read on for a comprehensive list of user-facing changes, including many other smaller improvements, CPython optimizations, deprecations, and potential porting issues.
The new ensurepip module defined in PEP provides a standard cross-platform mechanism to bootstrap the pip installer into Python installations and virtual environments. The version of pip included with Python 3. By default, the commands pipX and pipX. Y will be installed on all platforms where X. Y stands for the version of the Python installation , along with the pip Python package and its dependencies.
On Windows and in virtual environments on all platforms, the unversioned pip command will also be installed. On other platforms, the system wide unversioned pip command typically refers to the separately installed Python 2 version.
The pyvenv command line utility and the venv module make use of the ensurepip module to make pip readily available in virtual environments. When using the command line utility, pip is installed by default, while when using the venv module API installation of pip must be requested explicitly.
This behaviour can be controlled through configure options, and overridden through Makefile options. On Windows and Mac OS X, the CPython installers now default to installing pip along with CPython itself users may opt out of installing it during the installation process. Window users will need to opt in to the automatic PATH modifications to have pip available from the command line by default, otherwise it can still be accessed through the Python launcher for Windows as py -m pip. As discussed in the PEP , platform packagers may choose not to install these commands by default, as long as, when invoked, they provide clear and simple directions on how to install them on that platform usually using the system package manager.
To avoid conflicts between parallel Python 2 and Python 3 installations, only the versioned pip3 and pip3. As part of this change, the Installing Python Modules and Distributing Python Modules sections of the documentation have been completely redesigned as short getting started and FAQ documents.
Most packaging documentation has now been moved out to the Python Packaging Authority maintained Python Packaging User Guide and the documentation of the individual projects. However, as this migration is currently still incomplete, the legacy versions of those guides remaining available as Installing Python Modules Legacy version and Distributing Python Modules Legacy version.
PEP makes newly created file descriptors non-inheritable. In general, this is the behavior an application will want: However, there are occasions when inheritance is desired. To support these cases, the following new functions and methods are available:. Since it was first introduced, the codecs module has always been intended to operate as a type-neutral dynamic encoding and decoding system. However, its close coupling with the Python text model, especially the type restricted convenience methods on the builtin str , bytes and bytearray types, has historically obscured that fact.
As a key step in clarifying the situation, the codecs. These functions have existed in the codecs module and have been covered by the regression test suite since Python 2. In a related change, whenever it is feasible without breaking backwards compatibility, exceptions raised during encoding and decoding operations are wrapped in a chained exception of the same type that mentions the name of the codec responsible for producing the error:.
Finally, as the examples above show, these improvements have permitted the restoration of the convenience aliases for the non-Unicode codecs that were themselves restored in Python 3. This means that encoding binary data to and from its hexadecimal representation for example can now be written as:. The binary and text transforms provided in the standard library are detailed in Binary Transforms and Text Transforms.
Contributed by Nick Coghlan in issue , issue , issue and issue PEP provides an encapsulation of the information about a module that the import machinery will use to load it that is, a module specification. This helps simplify both the import implementation and several import-related APIs. The change is also a stepping stone for several future import-related improvements.
The public-facing changes from the PEP are entirely backward-compatible. Furthermore, they should be transparent to everyone but importer authors. Key finder and loader methods have been deprecated, but they will continue working.
New importers should use the new methods described in the PEP. Existing importers should be updated to implement the new methods.
See the Deprecated section for a list of methods that should be replaced and their replacements. The new asyncio module defined in PEP provides a standard pluggable event loop model for Python, providing solid asynchronous IO support in the standard library, and making it easier for other event loop implementations to interoperate with the standard library and each other.
The new ensurepip module is the primary infrastructure for the PEP implementation. In the normal course of events end users will not need to interact with this module, but it can be used to manually bootstrap pip if the automated bootstrapping into an installation or virtual environment was declined.
If the installation has Internet access, after ensurepip is run the bundled pip can be used to upgrade pip to a more recent release than the bundled one. Note that such an upgraded version of pip is considered to be a separately installed package and will not be removed if Python is uninstalled. The module is named ensure pip because if called when pip is already installed, it does nothing. It also has an --upgrade option that will cause it to install the bundled copy of pip if the existing installed version of pip is older than the bundled copy.
The new enum module defined in PEP provides a standard implementation of enumeration types, allowing other modules such as socket to provide more informative error messages and better debugging support by replacing opaque integer constants with backwards compatible enumeration values. The new pathlib module offers classes representing filesystem paths with semantics appropriate for different operating systems.
The new statistics module defined in PEP offers some core statistics functionality directly in the standard library. This module supports calculation of the mean, median, mode, variance and standard deviation of a data series. The new tracemalloc module defined in PEP is a debug tool to trace memory blocks allocated by Python. It provides the following information:. ABCMeta , but is simpler to type and easier to read. Contributed by Bruno Dupuis in issue The getparams method now returns a namedtuple rather than a plain tuple.
Contributed by Claudiu Popa in issue Contributed by Serhiy Storchacha in issue The writeframesraw and writeframes methods now accept any bytes-like object.
Contributed by Serhiy Storchaka in issue The FileType class now accepts encoding and errors arguments, which are passed through to open. Contributed by Lucas Maystre in issue New byteswap function converts big-endian samples to little-endian and vice versa. All audioop functions now accept any bytes-like object. Strings are not accepted: The encoding and decoding functions in base64 now accept any bytes-like object in cases where it previously required a bytes or bytearray instance.
Contributed by Nick Coghlan in issue The a85 functions have options that can be used to make them compatible with the variants of the Ascii85 encoding, including the Adobe variant.
Contributed by Vinay Sajip in issue Contributed by Brian Landers and Serhiy Storchaka in issue Contributed by Raymond Hettinger in issue and Zero Piraeus in issue Using the context manager, the sys. StringIO , to a string. The latter can be especially useful, for example, to capture output from a function that was written to implement a command line interface.
It is recommended only for utility scripts because it affects the global state of sys. Contributed by Raymond Hettinger in issue The contextlib documentation has also been updated to include a discussion of the differences between single use, reusable and reentrant context managers.
When used in a with statement, the close method of the database object will be called automatically at the end of the block. Contributed by Claudiu Popa and Nick Coghlan in issue The dis module is now built around an Instruction class that provides object oriented access to the details of each individual bytecode operation.
Thus it is now possible to write a program that inspects and manipulates a bytecode object in ways different from those provided by the dis module itself. The various display tools in the dis module have been rewritten to use these new components. In addition, a new application-friendly class Bytecode provides an object-oriented API for inspecting bytecode in both in human-readable form and for iterating over instructions. But it also has a dis method, equivalent to calling dis on the constructor argument, but returned as a multi-line string:.
Contributed by Larry Hastings in issue David Murray and Daniel Urban in issue The doctest command line interface now uses argparse , and has two new options, -o and -f. David Murray in issue Contributed by Zachary Ware in issue It does not accept the maxheaderlen argument, but does accept the unixfrom and policy arguments. When specified, the associated header will be updated without changing its location in the list of headers. For backward compatibility, the default is False.
These classes provide a number of new methods that make extracting content from and inserting content into email messages much easier.
These API additions complete the bulk of the work that was planned as part of the email6 project. The currently provisional API is scheduled to become final in Python 3. Contributed by Mark Levitt in issue