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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 _lreg_bokeh(self, **kwargs):
 """ Returns a Bokeh linear regression line """

        try:
            ds2 = self._duplicate_()
            ds2.timestamps(ds2.x)
            ds2.lreg("Timestamps", ds2.y)
            ds2.drop(ds2.y)
            ds2.df = ds2.df.rename(columns={'Regression': ds2.y})
            if "date_format" in self.chart_style:
                ds2.date("Date", format=self.chart_style["date_format"])
            c = ds2.line_()
            return c
        except Exception as e:
            self.err(e, "Can not draw linear regression chart")