def __init__(self, values: Optional[Collection[str]] = None) -> None:
        """Create a new instance of :class:`CaseInsensitiveSet` with the given *values*.

        :param values: values to be added to the set.
        """
        self._values: Dict[str, str] = {}
        for v in values or ():
            self.add(v)
Create a new instance of :class:`CaseInsensitiveSet` with the given *values*.

        :param values: values to be added to the set.
        
patroni/collections.py