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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 rewrite_to_secure_url(url, secure_base=None):
 """ Rewrite URL to a Secure URL @param url URL to be rewritten to a secure URL. @param secure_base: Base URL of secure site (defaults to CFG_SITE_SECURE_URL). """

    if secure_base is None:
        secure_base = cfg.get('CFG_SITE_SECURE_URL')
    url_parts = list(urlparse(url))
    url_secure_parts = urlparse(secure_base)
    url_parts[0] = url_secure_parts[0]
    url_parts[1] = url_secure_parts[1]
    return urlunparse(url_parts)