Constant lexical_write_integer::format::SAGE_STRING

pub const SAGE_STRING: u128 = NumberFormatBuilder::new().digit_separator(num::NonZeroU8::new(b'_')).internal_digit_separator(true).build(); // 202_824_096_038_269_144_926_504_985_034_764u128

Number format to parse a Sage float from string.