If this Foreign income was during the non-resident period, then you report it under the Statement of World Income, not on Line10400. and do not deduct the tax.
If the income was during the resident period then you will include it on Line 10400 and will deduct the taxes associated with it based on the tax treaty with the country.
If I understand your situation correctly, the foreign income you earned was after you left Canada, so you do not include it in your income.
I hope this was helpful
