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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 xml_str_to_dict(s):
 """ Transforms an XML string it to python-zimbra dict format For format, see: https://github.com/Zimbra-Community/python-zimbra/blob/master/README.md :param: a string, containing XML :returns: a dict, with python-zimbra format """

    xml = minidom.parseString(s)
    return pythonzimbra.tools.xmlserializer.dom_to_dict(xml.firstChild)