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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 buildEXPmask(self, chip, dqarr):
 """ Builds a weight mask from an input DQ array and the exposure time per pixel for this chip. """

        log.info("Applying EXPTIME weighting to DQ mask for chip %s" %
                 chip)
        #exparr = self.getexptimeimg(chip)
        exparr = self._image[self.scienceExt,chip]._exptime
        expmask = exparr*dqarr

        return expmask.astype(np.float32)