def auth_by_external_key(account_external_key, payment_method_id = nil, user = nil, reason = nil, comment = nil, options = {}, refresh_options = nil)
        @transaction_type = 'AUTHORIZE'
        query_map = {:externalKey => account_external_key}
        create_initial_transaction("#{Account::KILLBILL_API_ACCOUNTS_PREFIX}/payments", query_map, payment_method_id, user, reason, comment, options, refresh_options)