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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 _extract_node_text(node):
 """Extract text from a given lxml node."""


    texts = map(
        six.text_type.strip, map(six.text_type, map(unescape, node.xpath(".//text()")))
    )
    return " ".join(text for text in texts if text)