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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 get_pixel_coordinates(self, point, ccdnum):
 """ Retrieves the pixel location of a point within the current HDUList given the location in the original FITS image. This takes into account that the image may be a cutout of a larger original. Args: point: tuple(float, float) (x, y) in original. Returns: (x, y) pixel in this image. @param extno: the extno from the original Mosaic that the x/y coordinates are from. """

        hdulist_index = self.get_hdulist_idx(ccdnum)
        if isinstance(point[0], Quantity) and isinstance(point[1], Quantity):
            pix_point = point[0].value, point[1].value
        else:
            pix_point = point
        if self.reading.inverted:
            pix_point = self.reading.obs.naxis1 - pix_point[0] +1 , self.reading.obs.naxis2 - pix_point[1] + 1

        (x, y) = self.hdulist[hdulist_index].converter.convert(pix_point)
        return x, y, hdulist_index