def _format_timeframe(self, timeframe: TimeFrameLiteral, delta: int) -> str:
        """Slovak aware time frame format function, takes into account
        the differences between past and future forms."""
        abs_delta = abs(delta)
        form = self.timeframes[timeframe]

        if isinstance(form, str):
            return form.format(abs_delta)

        if delta == 0:
            key = "zero"  # And *never* use 0 in the singular!
        elif delta < 0:
            key = "past"
        else:
            if "future-singular" not in form:
                key = "future"
            elif 2 <= abs_delta % 10 <= 4 and (
                abs_delta % 100 < 10 or abs_delta % 100 >= 20
            ):
                key = "future-singular"
            else:
                key = "future-paucal"

        form: str = form[key]
        return form.format(abs_delta)
Slovak aware time frame format function, takes into account
        the differences between past and future forms.
arrow/locales.py