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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 extract_tag_metadata(self, el):
 """Extract meta data."""


        if self.type == 'odp':
            if el.namespace and el.namespace == self.namespaces['draw'] and el.name == 'page-thumbnail':
                name = el.attrs.get('draw:page-number', '')
                self.additional_context = 'slide{}:'.format(name)
        super().extract_tag_metadata(el)