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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _field_lookups(model, status=None):
 """ Abstraction of field lookups for managers. Returns a dictionary of field lookups for a queryset. The lookups will always filter by site. Optionally, if ``status`` is passed to the function the objects will also be filtered by the given status. This function saves from having to make two different on-site and published Managers each for `Topic` and `Question`, and having to move Managers out of the `FAQBase` model and into each of the `Topic` and `Question` models. """

    # Import models here to avoid circular import fail.
    from faq.models import Topic, Question

    field_lookups = {}

    if model == Topic:
        field_lookups['sites__pk'] = settings.SITE_ID

    if model == Question:
        field_lookups['topic__sites__pk'] = settings.SITE_ID
        if status:
            field_lookups['topic__status'] = status

    # Both Topic & Question have a status field.
    if status:
        field_lookups['status'] = status

    return field_lookups