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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 mark_read(request, message_id, dispatch_id, hashed, redirect_to=None):
 """Handles mark message as read request. :param Request request: :param int message_id: :param int dispatch_id: :param str hashed: :param str redirect_to: :return: """

    if redirect_to is None:
        redirect_to = get_static_url('img/sitemessage/blank.png')

    return _generic_view(
        'handle_mark_read_request', sig_mark_read_failed,
        request, message_id, dispatch_id, hashed, redirect_to=redirect_to
    )