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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 add_unique_template_variables(self, options):
 """Update map template variables specific to a raster visual"""

        options.update(dict(
            tiles_url=self.tiles_url,
            tiles_size=self.tiles_size,
            tiles_minzoom=self.tiles_minzoom,
            tiles_maxzoom=self.tiles_maxzoom,
            tiles_bounds=self.tiles_bounds if self.tiles_bounds else 'undefined'))