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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 create_big_url(name):
 """ If name looks like a url, with an http, add an entry for it in BIG_URLS """

    # BIG side effect
    global BIG_URLS
    filemeta = get_url_filemeta(name)
    if not filemeta:
        return None
    filename = filemeta['filename']
    remote_size = filemeta['remote_size']
    url = filemeta['url']
    name = filename.split('.')
    name = (name[0] if name[0] not in ('', '.') else name[1]).replace(' ', '-')
    name = name.lower().strip()
    BIG_URLS[name] = (url, int(remote_size or -1), filename)
    return name