def env_true(var: str) -> bool:
        """Determine whether the given environment variable is "true".

        As env vars are strings, "true" means the string is one of a few set of
        values, case-insensitive:
            - "1"
            - "true"
            - "yes"
            - "y"
            - "on"

        Args:
            var: The environment variable to check.

        Returns:
            bool: Whether the environment variable is "true".
        """

        return os.environ.get(var, "").lower() in [
            "1",
            "true",
            "yes",
            "y",
            "on",
        ]
Determine whether the given environment variable is "true".

        As env vars are strings, "true" means the string is one of a few set of
        values, case-insensitive:
            - "1"
            - "true"
            - "yes"
            - "y"
            - "on"

        Args:
            var: The environment variable to check.

        Returns:
            bool: Whether the environment variable is "true".
        
tests/test.py