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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 isOnSilicon(self, ra_deg, dec_deg, padding_pix=DEFAULT_PADDING):
 """Returns True if the given location is observable with a science CCD. Parameters ra_deg : float Right Ascension (J2000) in decimal degrees. dec_deg : float Declination (J2000) in decimal degrees. padding : float Objects <= this many pixels off the edge of a channel are counted as inside. This allows one to compensate for the slight inaccuracy in `K2fov` that results from e.g. the lack of optical distortion modeling. """

        ch, col, row = self.getChannelColRow(ra_deg, dec_deg)
        # Modules 3 and 7 are no longer operational
        if ch in self.brokenChannels:
            return False
        # K2fov encodes the Fine Guidance Sensors (FGS) as
        # "channel" numbers 85-88; they are not science CCDs.
        if ch > 84:
            return False
        return self.colRowIsOnSciencePixel(col, row, padding_pix)