Return list of strings parsed from `content` attribute from ``<meta>``
    tags with given `meta_name`.

def parse_meta(content, meta_name, source_descr, content_attr_name="content"):
    """
    Return list of strings parsed from `content` attribute from ``<meta>``
    tags with given `meta_name`.
    """
    dom = dhtmlparser.parseString(content)

    meta_tags = dom.find(
        "meta",
        fn=lambda x: x.params.get("name", "").lower() == meta_name.lower()
    )

    return [
        SourceString(tag.params[content_attr_name], source_descr)
        for tag in meta_tags
        if content_attr_name in tag.params
    ]