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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 get_html_titles(index_page):
 """ Return list of titles parsed from HTML. Args: index_page (str):
 HTML content of the page you wish to analyze. Returns: list: List of :class:`.SourceString` objects. """

    dom = dhtmlparser.parseString(index_page)

    title_tags = dom.find("title")

    return [
        SourceString(tag.getContent().strip(), "HTML")
        for tag in title_tags
        if tag.getContent().strip()
    ]