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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 index(request, page):
 """Show the index page or any an offset of it."""

    days = []
    days_found = set()
    query = Entry.query.order_by(Entry.pub_date.desc())
    pagination = Pagination(query, PER_PAGE, page, "index")
    for entry in pagination.entries:
        day = date(*entry.pub_date.timetuple()[:3])
        if day not in days_found:
            days_found.add(day)
            days.append({"date": day, "entries": []})
        days[-1]["entries"].append(entry)
    return render_template("index.html", days=days, pagination=pagination)