Getting version from git repository

get_git_version.py

class Version:

    def __init__(self, master_ver, branch, git_hash):
        self.master_ver = master_ver
        self.branch = branch
        self.hash = git_hash

    @classmethod
    def from_str(cls, version_str):
        version = version_str.split('-')
        return cls(*version)

    def __str__(self):
        git_version = f'{self.master_ver}-{self.branch}' \
                      f'-{self.hash}'
        return git_version


def git_version(force=False):
    if os.path.isfile('.git_version') and not force:
        with open('.git_version', 'r') as f:
            git_version = Version.from_str(f.readline())
            return git_version
    current_git_branch = subprocess.getoutput(
        'git symbolic-ref --short HEAD'
        )
    if current_git_branch == 'master':
        git_version = subprocess.getoutput(
            'git describe --tags'
            )
    else:
        git_current_hash = subprocess.getoutput(
            'git rev-parse --short HEAD'
            )
        git_master_version = subprocess.getoutput(
            'git describe --tags origin/master'
            )
    return Version(git_master_version,
                   current_git_branch,
                   git_current_hash,
                   )


version = git_version()