else:

            return str(raw_value)

class AggregateSet(bc_query_compile.EvalAggregator):

    """Filter argument values that aren't unique."""

    __intypes__ = [object]

    def __init__(self, operands: List[bc_query_compile.EvalNode]) -> None:

       super().__init__(operands, set)

    def allocate(self, allocator: bc_query_execute.Allocator) -> None:

        """Allocate and save an index handle into result storage."""

        self.handle = allocator.allocate()

    def initialize(self, store: Store) -> None:

        """Prepare result storage for a new aggregation."""

        store[self.handle] = self.dtype()

        # self.dtype() is our return type, aka the second argument to __init__

        # above, aka the annotated return type of __call__.

    def update(self, store: Store, context: PostingContext) -> None:

        """Update existing storage with new result data."""

        value, = self.eval_args(context)

            store[self.handle].update(value)

        else:

            store[self.handle].add(value)

    def __call__(self, context: PostingContext) -> set:

        """Return the result for an aggregation."""

        return context.store[self.handle]  # type:ignore[no-any-return]

class _EnvironmentMixin:

    db_path = Path('Financial', 'Ledger', 'supporters.db')

    columns: EnvironmentColumns

    functions: EnvironmentFunctions

    @classmethod

    def with_config(cls, config: configmod.Config) -> Type['_EnvironmentMixin']:

        columns = cls.columns.copy()

        repo_path = config.repository_path()

        try:

            if repo_path is None:

                raise sqlite3.Error("no repository configured to host database")

            db_conn = sqlite3.connect(os.fspath(repo_path / cls.db_path))

        except (OSError, sqlite3.Error):

            columns['db_email'] = DBEmail