from datetime import datetime
import re

USER_PATTERN = re.compile(r"^[a-z_][a-z0-9_-]{0,31}$")

class SSHUser:
    user: str
    last_login: datetime | None

    def __repr__(self):
        return f"SSHUser(user='{self.user}', last_login={self.last_login})"

    def __init__(self, user: str):
        self.user = user
        self.last_login = None

    def validate(self):
        return USER_PATTERN.match(self.user) is not None