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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_value_enum(self, var, tag):
 """ supports adding variables to the xml Parameters var: The SubElement variable tag: The SubElement tag to which enum value is to be added Return None """

        if var['ValueEnum'][0] == 's0':
                numvalues_tag = etree.SubElement(tag, 'NumValues')
                numvalues_tag.text = str(int(var['ValueEnum'][-1][-1]) + 1)
        else:
            valueenum_tag = etree.SubElement(tag, 'ValueEnum')
            valueenum_tag.text = ''
            for value in var['ValueEnum']:
                valueenum_tag.text += value + ' '
            valueenum_tag.text = valueenum_tag.text[:-1]