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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 _add_additional_properties(position, properties_dict):
 """ Sets AdditionalProperties of the ProbModelXML. """

        add_prop = etree.SubElement(position, 'AdditionalProperties')
        for key, value in properties_dict.items():
            etree.SubElement(add_prop, 'Property', attrib={'name': key, 'value': value})