def METHOD_NAME(account_name: Account, account_types: AccountTypes) -> bool:
    """Return true if the given account is an income statement account.
    Income and expense accounts are income statement accounts.
    Args:
      account_name: A string, an account name.
      account_types: An instance of AccountTypes.
    Returns:
      A boolean, true if the account is an income statement account.
    """
    assert isinstance(account_name, str), "Account is not a string: {}".format(account_name)
    assert isinstance(account_types, AccountTypes), (
        "Account types has invalid type: {}".format(account_types))
    account_type = get_account_type(account_name)
    return account_type in (account_types.income,
                            account_types.expenses)