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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 get_schema_descendant( self, route: SchemaRoute) -> Optional[SchemaNode]: """Return descendant schema node or ``None`` if not found. Args: route: Schema route to the descendant node (relative to the receiver). """

        node = self
        for p in route:
            node = node.get_child(*p)
            if node is None:
                return None
        return node