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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 text(self, selector):
 """Return text result that executed by given css selector :param selector: `str` css selector :return: `list` or `None` """


        result = self.__bs4.select(selector)

        return [r.get_text() for r in result] \
            if result.__len__() > 1 else \
            result[0].get_text() if result.__len__() > 0 else None