Python3.5有什么新特性？

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Python 3.5.0a3

Python 3.5.0a3 was released on March 30th, 2015.

Major new features of the 3.5 series, compared to 3.4

Python 3.5 is still in development, and 3.5.0a1 is the second alpha release. Many new features are still being planned and written. Among the new major new features and changes in the 3.4 release series so far are

• PEP 461, adding support for "%-formatting" for bytes and bytearray objects
• PEP 465, a new operator (@) for matrix multiplication
• PEP 475, adding support for automatic retries of interrupted system calls
• PEP 471, os.scandir()

PEP 484, the typing module, a new standard for type annotations

from typing import TypeVar, Iterable, Tuple

T = TypeVar('T', int, float, complex)
Vector = Iterable[Tuple[T, T]]

def inproduct(v: Vector) -> T:
    return sum(x*y for x, y in v)