default MutableAccount getOrCreate(final Address address) {
    final MutableAccount account = getAccount(address);
    return account == null ? createAccount(address) : account;
  }
Retrieves the provided account if it exists, or create it if it doesn't.

@param address the address of the account.
@return the account {@code address}. If that account exists, it is returned as if by {@link
    #getAccount(Address)}, otherwise, it is created and returned as if by {@link
    #createAccount(Address)} (and thus all his fields will be zero/empty).
evm/src/main/java/org/hyperledger/besu/evm/worldstate/WorldUpdater.java