docs: def fms(x, y, z, context=None):
      """
      Return (x * y) - z, with a single rounding according to the current
      context.
  
      """
      return _apply_function_in_current_context(
          BigFloat,
          mpfr.mpfr_fms,
          (
              BigFloat._implicit_convert(x),
              BigFloat._implicit_convert(y),
              BigFloat._implicit_convert(z),
          ),
          context,
      )