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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_common_prefix(self, node1, node2):
 """Find common prefix between two nodes."""

        tokens1 = [item.strip() for item in node1.split(self.node_separator)]
        tokens2 = [item.strip() for item in node2.split(self.node_separator)]
        ret = []
        for token1, token2 in zip(tokens1, tokens2):
            if token1 == token2:
                ret.append(token1)
            else:
                break
        return self.node_separator.join(ret)