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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 show_current_metadata(self):
 """Show metadata of the current selected layer."""

        LOGGER.debug('Showing layer: ' + self.layer.name())
        keywords = KeywordIO(self.layer)
        content_html = keywords.to_message().to_html()
        full_html = html_header() + content_html + html_footer()
        self.metadata_preview_web_view.setHtml(full_html)