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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 _add_series_or_dataframe_operations(cls):
 """ Add the series or dataframe only operations to the cls; evaluate the doc strings again. """


        from pandas.core import window as rwindow

        @Appender(rwindow.rolling.__doc__)
        def rolling(self, window, min_periods=None, center=False,
                    win_type=None, on=None, axis=0, closed=None):
            axis = self._get_axis_number(axis)
            return rwindow.rolling(self, window=window,
                                   min_periods=min_periods,
                                   center=center, win_type=win_type,
                                   on=on, axis=axis, closed=closed)

        cls.rolling = rolling

        @Appender(rwindow.expanding.__doc__)
        def expanding(self, min_periods=1, center=False, axis=0):
            axis = self._get_axis_number(axis)
            return rwindow.expanding(self, min_periods=min_periods,
                                     center=center, axis=axis)

        cls.expanding = expanding

        @Appender(rwindow.ewm.__doc__)
        def ewm(self, com=None, span=None, halflife=None, alpha=None,
                min_periods=0, adjust=True, ignore_na=False,
                axis=0):
            axis = self._get_axis_number(axis)
            return rwindow.ewm(self, com=com, span=span, halflife=halflife,
                               alpha=alpha, min_periods=min_periods,
                               adjust=adjust, ignore_na=ignore_na, axis=axis)

        cls.ewm = ewm