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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 progress_bar_media():
 """ progress_bar_media simple tag return rendered script tag for javascript used by progress_bar """

    if PROGRESSBARUPLOAD_INCLUDE_JQUERY:
        js = ["http://code.jquery.com/jquery-1.8.3.min.js",]
    else:
        js = []
    js.append("js/progress_bar.js")
        
    m = Media(js=js)
    return m.render()