Function math_fraktur_encode 

pub fn math_fraktur_encode(payload: &str) -> String

Mathematical Fraktur (blackletter) alphabet — uppercase U+1D504, lowercase U+1D51E. Fraktur has holes at C/H/I/R/Z which are filled by U+212D ℭ, U+210C ℌ, U+2111 ℑ, U+211C ℜ, U+2128 ℨ.