invert method
Invert null of field is zero
Implementation
@override
Bls12Fp? invert() {
final modulus = pow([
BigInt.parse('0xb9feffffffffaaa9'),
BigInt.parse('0x1eabfffeb153ffff'),
BigInt.parse('0x6730d2a0f6b0f624'),
BigInt.parse('0x64774b84f38512bf'),
BigInt.parse('0x4b1ba7b6434bacd7'),
BigInt.parse('0x1a0111ea397fe69a'),
]);
if (isZero()) return null;
return modulus;
}