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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 geo(self):
 """Return a geopandas dataframe"""

        import geopandas as gpd
        from shapely.geometry.polygon import BaseGeometry
        from shapely.wkt import loads

        gdf = gpd.GeoDataFrame(self)

        first = next(gdf.iterrows())[1].geometry

        if isinstance(first, str):
            # We have a GeoDataframe, but the geometry column is still strings, so
            # it must be converted
            shapes = [ loads(row['geometry']) for i, row in gdf.iterrows()]

        elif not isinstance(first, BaseGeometry):
            # If we are reading a metatab package, the geometry column's type should be
            # 'geometry' which will give the geometry values class type of
            # rowpipe.valuetype.geo.ShapeValue. However, there are other
            # types of objects that have a 'shape' property.

            shapes = [row['geometry'].shape for i, row in gdf.iterrows()]

        else:
            shapes = gdf['geometry']

        gdf['geometry'] = gpd.GeoSeries(shapes)
        gdf.set_geometry('geometry')
        return gdf