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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 find_replace(self, node):
 """Try to find replace node for current node. Parameters node : docutil node Node to find replacement for. Returns ------- nodes : node or list of node The replacement nodes of current node. Returns None if no replacement can be found. """

        newnode = None
        if isinstance(node, nodes.Sequential):
            newnode = self.auto_toc_tree(node)
        elif isinstance(node, nodes.literal_block):
            newnode = self.auto_code_block(node)
        elif isinstance(node, nodes.literal):
            newnode = self.auto_inline_code(node)
        return newnode