import { bnSqrt } from "https://deno.land/x/polkadot@0.2.37/util/bn/index.ts";
Examples
import BN from 'https://esm.sh/bn.js@5.2.1';
import { bnSqrt } from 'https://deno.land/x/polkadot@0.2.37/util/mod.ts';
bnSqrt(new BN(16)).toString(); // => '4'