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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 request(input, representation, resolvers=None, get3d=False, tautomers=False, **kwargs):
 """Make a request to CIR and return the XML response. :param string input: Chemical identifier to resolve :param string representation: Desired output representation :param list(string) resolvers: (Optional) Ordered list of resolvers to use :param bool get3d: (Optional) Whether to return 3D coordinates (where applicable) :param bool tautomers: (Optional) Whether to return all tautomers :returns: XML response from CIR :rtype: Element :raises HTTPError: if CIR returns an error code :raises ParseError: if CIR response is uninterpretable """

    url = construct_api_url(input, representation, resolvers, get3d, tautomers, **kwargs)
    log.debug('Making request: %s', url)
    response = urlopen(url)
    return etree.parse(response).getroot()