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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 _assignSignature(self, chip):
 """Assign a unique signature for the image based on the instrument, detector, chip, and size this will be used to uniquely identify the appropriate static mask for the image. This also records the filename for the static mask to the outputNames dictionary. """

        sci_chip = self._image[self.scienceExt,chip]
        ny=sci_chip._naxis1
        nx=sci_chip._naxis2
        detnum = sci_chip.detnum
        instr=self._instrument

        sig=(instr+self._detector,(nx,ny),int(detnum)) #signature is a tuple
        sci_chip.signature=sig