golden hour

/usr/lib/python3.9/site-packages/dns

File/Folder	Size	Actions
__init__.py	1.62 KB
__pycache__	-
_asyncbackend.py	2.3 KB
_asyncio_backend.py	8.76 KB
_ddr.py	5.12 KB
_features.py	2.33 KB
_immutable_ctx.py	2.4 KB
asyncbackend.py	2.73 KB
asyncquery.py	26.22 KB
asyncresolver.py	17.43 KB
dnssec.py	39.74 KB
dnssecalgs	-
dnssectypes.py	1.76 KB
e164.py	3.88 KB
edns.py	14.91 KB
entropy.py	4.14 KB
enum.py	3.6 KB
exception.py	5.82 KB
flags.py	2.69 KB
grange.py	2.1 KB
immutable.py	1.97 KB
inet.py	5.64 KB
ipv4.py	2.49 KB
ipv6.py	6.45 KB
message.py	64.45 KB
name.py	41.67 KB
namedict.py	3.91 KB
nameserver.py	9.68 KB
node.py	12.37 KB
opcode.py	2.67 KB
query.py	53.55 KB
quic	-
rcode.py	4.06 KB
rdata.py	28.77 KB
rdataclass.py	2.91 KB
rdataset.py	16.36 KB
rdatatype.py	7.17 KB
rdtypes	-
renderer.py	10.99 KB
resolver.py	71.83 KB
reversename.py	3.74 KB
rrset.py	8.96 KB
serial.py	3.52 KB
set.py	8.88 KB
tokenizer.py	23.03 KB
transaction.py	22.11 KB
tsig.py	11.15 KB
tsigkeyring.py	2.57 KB
ttl.py	2.91 KB
update.py	11.96 KB
version.py	1.88 KB
versioned.py	11.49 KB
win32util.py	8.89 KB
wire.py	2.76 KB
xfr.py	12.96 KB
zone.py	50.87 KB
zonefile.py	27.27 KB
zonetypes.py	690 B

Edit: _features.py

# Copyright (C) Dnspython Contributors, see LICENSE for text of ISC license

import importlib.metadata
import itertools
import string
from typing import Dict, List, Tuple

def _tuple_from_text(version: str) -> Tuple:
    text_parts = version.split(".")
    int_parts = []
    for text_part in text_parts:
        digit_prefix = "".join(
            itertools.takewhile(lambda x: x in string.digits, text_part)
        )
        try:
            int_parts.append(int(digit_prefix))
        except Exception:
            break
    return tuple(int_parts)

def _version_check(
    requirement: str,
) -> bool:
    """Is the requirement fulfilled?

The requirement must be of the form

package>=version
    """
    package, minimum = requirement.split(">=")
    try:
        version = importlib.metadata.version(package)
    except Exception:
        return False
    t_version = _tuple_from_text(version)
    t_minimum = _tuple_from_text(minimum)
    if t_version < t_minimum:
        return False
    return True

_cache: Dict[str, bool] = {}

def have(feature: str) -> bool:
    """Is *feature* available?

This tests if all optional packages needed for the
    feature are available and recent enough.

Returns ``True`` if the feature is available,
    and ``False`` if it is not or if metadata is
    missing.
    """
    value = _cache.get(feature)
    if value is not None:
        return value
    requirements = _requirements.get(feature)
    if requirements is None:
        # we make a cache entry here for consistency not performance
        _cache[feature] = False
        return False
    ok = True
    for requirement in requirements:
        if not _version_check(requirement):
            ok = False
            break
    _cache[feature] = ok
    return ok

def force(feature: str, enabled: bool) -> None:
    """Force the status of *feature* to be *enabled*.

This method is provided as a workaround for any cases
    where importlib.metadata is ineffective, or for testing.
    """
    _cache[feature] = enabled

_requirements: Dict[str, List[str]] = {
    ### BEGIN generated requirements
    "dnssec": ["cryptography>=41"],
    "doh": ["httpcore>=1.0.0", "httpx>=0.26.0", "h2>=4.1.0"],
    "doq": ["aioquic>=0.9.25"],
    "idna": ["idna>=3.6"],
    "trio": ["trio>=0.23"],
    "wmi": ["wmi>=1.5.1"],
    ### END generated requirements
}