def __init__(self, prefix: str):
        """Initialises the PrefixFilter class.

        Args:
            prefix: The prefix to filter on.
        """
        if not isinstance(prefix, str):
            raise TypeError("`SETTINGS_FILE_PREFIX` must be str")
        self.prefix = f"{upperfy(prefix)}_"
Initialises the PrefixFilter class.

        Args:
            prefix: The prefix to filter on.
        
dynaconf/strategies/filtering.py