def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)

        # Limit `year_of_addition` field values to the current year and the next two years.
        now = tz.now()
        min_year = now.year
        max_year = min_year + 2
        self.fields["year_of_addition"].validators = [
            MinValueValidator(min_year),
            MaxValueValidator(max_year),
        ]
        self.fields["year_of_addition"].widget = AdminIntegerFieldWidget(
            attrs={
                "min": min_year,
                "max": max_year,
            },
        )