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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 compute_wcslin(self,undistort=True):
 """ Compute the undistorted WCS based solely on the known distortion model information associated with the WCS. """

        for chip in range(1,self._numchips+1,1):
            sci_chip = self._image[self.scienceExt,chip]
            chip_wcs = sci_chip.wcs.copy()

            if chip_wcs.sip is None or not undistort or chip_wcs.instrument=='DEFAULT':
                chip_wcs.sip = None
                chip_wcs.cpdis1 = None
                chip_wcs.cpdis2 = None
                chip_wcs.det2im = None
                undistort=False

            # compute the undistorted 'natural' plate scale for this chip
            wcslin = distortion.utils.output_wcs([chip_wcs],undistort=undistort)
            sci_chip.wcslin_pscale = wcslin.pscale