getBalanceOfAddress(address) {
    let balance = 0;

    for (const block of this.chain) {
      for (const trans of block.transactions) {
        if (trans.fromAddress === address) {
          balance -= trans.amount;
        }

        if (trans.toAddress === address) {
          balance += trans.amount;
        }
      }
    }

    debug('getBalanceOfAdrees: %s', balance);
    return balance;
  }
Returns the balance of a given wallet address.

@param {string} address
@returns {number} The balance of the wallet