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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 have_thumbnail(self, fitsimage, image):
 """Returns True if we already have a thumbnail version of this image cached, False otherwise. """

        chname = self.fv.get_channel_name(fitsimage)

        # Look up our version of the thumb
        idx = image.get('idx', None)
        path = image.get('path', None)
        if path is not None:
            path = os.path.abspath(path)
            name = iohelper.name_image_from_path(path, idx=idx)
        else:
            name = 'NoName'

        # get image name
        name = image.get('name', name)

        thumbkey = self.get_thumb_key(chname, name, path)
        with self.thmblock:
            return thumbkey in self.thumb_dict