py2dataclasses 3.14.112

PEP-557 compatible dataclasses backport for Python 2.7+

py2dataclasses

This project is a PEP-557 compatible dataclass implementation for Python 2.7.

Usage

On Python 2.7 there is no annotation syntax (x: int), so fields are declared using field() descriptors:

from dataclasses import dataclass, field

@dataclass
class Point(object):
    x = field(int)
    y = field(int)

p = Point(3, 4)
print(p)        # Point(x=3, y=4)
print(p.x)      # 3
print(p == Point(3, 4))  # True

Disclaimer

Sometimes systems have a proprietary legacy that is not possible to port to newer versions of languages. But people still need to work, systems using python 2 still have to be supported and extended.

⚠ WARNING

• Please, DO NOT use Python 2.7 in 2026

Development

• This is quite a straightforward convertion of dataclasses into a py2 syntax/standard done initially by neural network, and after that it was reviewed, fixed and finished by human.
• Tests are taken from the cpython 3.14 branch and converted to py2

Testing

• This project aims to pass all the tests from Python 3.14
• It also aims to pass all backported tests.