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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 css_text(self, path, default=NULL, smart=False, normalize_space=True):
 """ Get normalized text of node which matches the css path. """


        try:
            return get_node_text(self.css_one(path), smart=smart,
                                 normalize_space=normalize_space)
        except IndexError:
            if default is NULL:
                raise
            else:
                return default