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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 timestamps(self, col: str, **kwargs):
 """" Add a timestamps column from a date column :param col: name of the timestamps column to add :type col: str :param \*\*kwargs: keyword arguments for ``pd.to_datetime`` for date conversions :type \*\*kwargs: optional :example: ``ds.timestamps("mycol")`` """

        try:
            name = "Timestamps"
            if "name" in kwargs:
                name = kwargs["name"]
            if "errors" not in kwargs:
                kwargs["errors"] = "coerce"
            if "unit" in kwargs:
                kwargs["unit"] = "ms"
            try:
                self.df[col] = pd.to_datetime(self.df[col], **kwargs)
            except TypeError:
                pass
            ts = []
            for el in self.df[col]:
                ts.append(arrow.get(el).timestamp)
            self.df[name] = ts
        except Exception as e:
            self.err(e, "Can not convert to timestamps")