from typing import Dict
from typing import Any


def get_only_value(d: Dict) -> Any:
    """Get the value from dict that only has one key.

    Args:
        d: Dict that only has one key.

    Returns:
        Any: Value of the only key.
    """
    values = list(d.values())
    if not values or len(values) != 1:
        return None
    return values[0]