old_contents: from geopandas import GeoDataFrame
  
  from ..utils.geom_utils import generate_index, generate_geometry
  
  
  class CartoDataFrame(GeoDataFrame):
  
      def __init__(self, *args, **kwargs):
          super(CartoDataFrame, self).__init__(*args, **kwargs)
  
      @staticmethod
      def from_carto(*args, **kwargs):
          from ..io.carto import read_carto
          return read_carto(*args, **kwargs)
  
      @classmethod
      def from_file(cls, filename, **kwargs):
          gdf = GeoDataFrame.from_file(filename, **kwargs)
          return cls(gdf)
  
      @property
      def _constructor(self):
          return CartoDataFrame
          
      @classmethod
      def from_features(cls, features, **kwargs):
          gdf = GeoDataFrame.from_features(features, **kwargs)
          return cls(gdf)
  
      def to_carto(self, *args, **kwargs):
          from ..io.carto import to_carto
          return to_carto(self, *args, **kwargs)
  
      def convert(self, index_column=None, geom_column=None, lnglat_columns=None,
                  drop_index=True, drop_geom=True, drop_lnglat=True):
          # Magic function
          generate_index(self, index_column, drop_index)
          generate_geometry(self, geom_column, lnglat_columns, drop_geom, drop_lnglat)
          return self
  
      def viz(self, *args, **kwargs):
          from ..viz import Map, Layer
          return Map(Layer(self, *args, **kwargs))
  
new_contents: from geopandas import GeoDataFrame
  
  from ..utils.geom_utils import generate_index, generate_geometry
  
  
  class CartoDataFrame(GeoDataFrame):
  
      def __init__(self, *args, **kwargs):
          super(CartoDataFrame, self).__init__(*args, **kwargs)
  
      @staticmethod
      def from_carto(*args, **kwargs):
          from ..io.carto import read_carto
          return read_carto(*args, **kwargs)
  
      @classmethod
      def from_file(cls, filename, **kwargs):
          gdf = GeoDataFrame.from_file(filename, **kwargs)
          return cls(gdf)
  
      @property
      def _constructor(self):
          return CartoDataFrame
  
      @classmethod
      def from_features(cls, features, **kwargs):
          gdf = GeoDataFrame.from_features(features, **kwargs)
          return cls(gdf)
  
      def to_carto(self, *args, **kwargs):
          from ..io.carto import to_carto
          return to_carto(self, *args, **kwargs)
  
      def convert(self, index_column=None, geom_column=None, lnglat_columns=None,
                  drop_index=True, drop_geom=True, drop_lnglat=True):
          # Magic function
          generate_index(self, index_column, drop_index)
          generate_geometry(self, geom_column, lnglat_columns, drop_geom, drop_lnglat)
          return self
  
      def viz(self, *args, **kwargs):
          from ..viz import Map, Layer
          return Map(Layer(self, *args, **kwargs))
  
subject: Fix linter issue