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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 bootstrap_javascript(jquery=None):
 """ Return HTML for Bootstrap JavaScript. Adjust url in settings. If no url is returned, we don't want this statement to return any HTML. This is intended behavior. Default value: ``None`` This value is configurable, see Settings section **Tag name**:: bootstrap_javascript **Parameters**: :jquery: Truthy to include jQuery as well as Bootstrap **Usage**:: {% bootstrap_javascript %} **Example**:: {% bootstrap_javascript jquery=1 %} """


    javascript = ""
    # See if we have to include jQuery
    if jquery is None:
        jquery = get_bootstrap_setting("include_jquery", False)
    # NOTE: No async on scripts, not mature enough. See issue #52 and #56
    if jquery:
        url = bootstrap_jquery_url()
        if url:
            javascript += render_script_tag(url)
    url = bootstrap_javascript_url()
    if url:
        javascript += render_script_tag(url)
    return mark_safe(javascript)