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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 over(self, window):
 """ Define a windowing column. :param window: a :class:`WindowSpec` :return: a Column """

        from pyspark.sql.window import WindowSpec
        if not isinstance(window, WindowSpec):
            raise TypeError("window should be WindowSpec")
        jc = self._jc.over(window._jspec)
        return Column(jc)