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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 isElement(self, node, name, nsuri=None):
 """Return true if the given node is an element with the given name and optional namespace uri."""

        if node.nodeType != node.ELEMENT_NODE:
            return 0
        return node.localName == name and \
               (nsuri is None or self.nsUriMatch(node.namespaceURI, nsuri))