Comment by js2

Challenge accepted:

    from dataclasses import dataclass
    
    @dataclass(frozen=True, order=True)
    class AppVersion:
        major: int = 0
        minor: int = 0
        patch: int = 0
    
        @classmethod
        def from_string(cls, version_string: str):
            return cls(*[int(x) for x in version_string.split(".")])
    
        def __str__(self):
            return f"{self.major}.{self.minor}.{self.patch}"

Before dataclasses you could've used namedtuples, at a loss of attribute typing and default initializer:

    from collections import namedtuple
    
    class AppVersion(namedtuple("AppVersion", "major minor patch")):

        @classmethod
        def from_string(cls, version_string: str):
            parts = [int(x) for x in version_string.split(".")] + [0, 0]
            return cls(*parts[:3])
    
        def __str__(self):
            return f"{self.major}.{self.minor}.{self.patch}"