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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 url_assembler(query_string, no_redirect=0, no_html=0, skip_disambig=0):
 """Assembler of parameters for building request query. Args: query_string: Query to be passed to DuckDuckGo API. no_redirect: Skip HTTP redirects (for !bang commands). Default - False. no_html: Remove HTML from text, e.g. bold and italics. Default - False. skip_disambig: Skip disambiguation (D) Type. Default - False. Returns: A “percent-encoded” string which is used as a part of the query. """

    params = [('q', query_string.encode("utf-8")), ('format', 'json')]

    if no_redirect:
        params.append(('no_redirect', 1))
    if no_html:
        params.append(('no_html', 1))
    if skip_disambig:
        params.append(('skip_disambig', 1))

    return '/?' + urlencode(params)