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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 _setup(self, layers, layer_idx):
 """Setups layers once geometry types and data types are known, and when a map is requested to be rendered from zero or more data layers"""

        basemap = layers[0]

        # if color not specified, choose a default
        if self.time:
            # default time/torque color
            self.color = self.color or '#2752ff'
        else:
            self.color = self.color or DEFAULT_COLORS[layer_idx]

        if isinstance(self.size, (int, float)):
            if self.geom_type == 'point':
                self.size = self.size or 4
            else:
                self.size = self.size or 1.5

        # choose appropriate scheme if not already specified
        if (not self.scheme) and (self.color in self.style_cols):
            self._choose_scheme()

        if self.time:
            self._setup_time(basemap)
        else:
            # use turbo-carto for non-animated maps
            self.cartocss = self._get_cartocss(basemap)