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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 query_entries( queryset=None, year=None, month=None, day=None, category=None, category_slug=None, tag=None, tag_slug=None, author=None, author_slug=None, future=False, order=None, orderby=None, limit=None, ):
 """ Query the entries using a set of predefined filters. This interface is mainly used by the ``get_entries`` template tag. """

    if queryset is None:
        queryset = get_entry_model().objects.all()

    if appsettings.FLUENT_BLOGS_FILTER_SITE_ID:
        queryset = queryset.parent_site(settings.SITE_ID)

    if not future:
        queryset = queryset.published()

    if year:
        queryset = queryset.filter(publication_date__year=year)
    if month:
        queryset = queryset.filter(publication_date__month=month)
    if day:
        queryset = queryset.filter(publication_date__day=day)

    # The main category/tag/author filters
    if category:
        if isinstance(category, basestring):
            queryset = queryset.categories(category)
        elif isinstance(category, (int, long)):
            queryset = queryset.filter(categories=category)
        else:
            raise ValueError("Expected slug or ID for the 'category' parameter")
    if category_slug:
        queryset = queryset.categories(category)

    if tag:
        if isinstance(tag, basestring):
            queryset = queryset.tagged(tag)
        elif isinstance(tag, (int, long)):
            queryset = queryset.filter(tags=tag)
        else:
            raise ValueError("Expected slug or ID for 'tag' parameter.")
    if tag_slug:
        queryset = queryset.tagged(tag)

    if author:
        if isinstance(author, basestring):
            queryset = queryset.authors(author)
        elif isinstance(author, (int, long)):
            queryset = queryset.filter(author=author)
        else:
            raise ValueError("Expected slug or ID for 'author' parameter.")
    if author_slug:
        queryset = queryset.authors(author_slug)

    # Ordering
    if orderby:
        queryset = queryset.order_by(*_get_order_by(order, orderby, ENTRY_ORDER_BY_FIELDS))
    else:
        queryset = queryset.order_by('-publication_date')

    # Limit
    if limit:
        queryset = queryset[:limit]

    return queryset