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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 _close_list(self):
 """ Add an close list tag corresponding to the currently open list found in current_parent_element. """

        list_type = self.current_parent_element['attrs']['class']
        tag = LIST_TYPES[list_type]

        html = '</{t}>'.format(
            t=tag
        )
        self.cleaned_html += html
        self.current_parent_element['tag'] = ''
        self.current_parent_element['attrs'] = {}