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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 normalize_whitespace(self, value):
 """Normalizes whitespace; called if ``ignore_ws`` is true."""

        if isinstance(value, unicode):
            return u" ".join(
                x for x in re.split(r'\s+', value, flags=re.UNICODE) if
                len(x)
            )
        else:
            return " ".join(value.split())