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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 determine_offset(self):
 """Determines the offset of the contours w.r.t. other data columns Notes ----- - the "frame" column of `rtdc_dataset` is compared to the first contour in the contour text file to determine an offset by one event - modifies the property `event_offset` and sets `_initialized` to `True` """

        # In case of regular RTDC, the first contour is
        # missing. In case of fRTDC, it is there, so we
        # might have an offset. We find out if the first
        # contour frame is missing by comparing it to
        # the "frame" column of the rtdc dataset.
        fref = self._contour_data.get_frame(0)
        f0 = self.frame[0]
        f1 = self.frame[1]
        # Use allclose to avoid float/integer comparison problems
        if np.allclose(fref, f0):
            self.event_offset = 0
        elif np.allclose(fref, f1):
            self.event_offset = 1
        else:
            msg = "Contour data has unknown offset (frame {})!".format(fref)
            raise IndexError(msg)
        self._initialized = True