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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 verify_draft_url(url):
 """ Return ``True`` if the given URL has a valid draft mode HMAC in its querystring. """

    url = urlparse.urlparse(url)
    # QueryDict requires a bytestring as its first argument
    query = QueryDict(force_bytes(url.query))
    # TODO Support legacy 'edit' param name for now
    preview_hmac = query.get('preview') or query.get('edit')
    if preview_hmac:
        salt, hmac = preview_hmac.split(':')
        return hmac == get_draft_hmac(salt, url.path)
    return False