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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 _check_root_tag(self, root):
 """Check that the XML element tree has a supported root element. Args: root (etree.Element) Raises: UnsupportedRootElementError """

        supported = self.supported_tags()
        if root.tag in supported:
            return

        error = "Document root element ({0}) not one of ({1})"
        raise UnsupportedRootElementError(
            message=error.format(root.tag, supported),
            expected=supported,
            found=root.tag,
        )