EPSG:4275 - NTF

{
  "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json",
  "type": "GeographicCRS",
  "name": "NTF",
  "datum": {
    "type": "GeodeticReferenceFrame",
    "name": "Nouvelle Triangulation Francaise",
    "ellipsoid": {
      "name": "Clarke 1880 (IGN)",
      "semi_major_axis": 6378249.2,
      "semi_minor_axis": 6356515
    }
  },
  "coordinate_system": {
    "subtype": "ellipsoidal",
    "axis": [
      {
        "name": "Geodetic latitude",
        "abbreviation": "Lat",
        "direction": "north",
        "unit": "degree"
      },
      {
        "name": "Geodetic longitude",
        "abbreviation": "Lon",
        "direction": "east",
        "unit": "degree"
      }
    ]
  },
  "scope": "Geodesy.",
  "area": "France - onshore - mainland and Corsica.",
  "bbox": {
    "south_latitude": 41.31,
    "west_longitude": -4.87,
    "north_latitude": 51.14,
    "east_longitude": 9.63
  },
  "id": {
    "authority": "EPSG",
    "code": 4275
  }
}

{'crs_wkt': 'GEOGCRS["NTF",DATUM["Nouvelle Triangulation '
            'Francaise",ELLIPSOID["Clarke 1880 '
            '(IGN)",6378249.2,293.466021293627,LENGTHUNIT["metre",1]]],PRIMEM["Greenwich",0,ANGLEUNIT["degree",0.0174532925199433]],CS[ellipsoidal,2],AXIS["geodetic '
            'latitude '
            '(Lat)",north,ORDER[1],ANGLEUNIT["degree",0.0174532925199433]],AXIS["geodetic '
            'longitude '
            '(Lon)",east,ORDER[2],ANGLEUNIT["degree",0.0174532925199433]],USAGE[SCOPE["Geodesy."],AREA["France '
            '- onshore - mainland and '
            'Corsica."],BBOX[41.31,-4.87,51.14,9.63]],ID["EPSG",4275]]',
 'geographic_crs_name': 'NTF',
 'grid_mapping_name': 'latitude_longitude',
 'horizontal_datum_name': 'Nouvelle Triangulation Francaise',
 'inverse_flattening': 293.4660212936269,
 'longitude_of_prime_meridian': 0.0,
 'prime_meridian_name': 'Greenwich',
 'reference_ellipsoid_name': 'Clarke 1880 (IGN)',
 'semi_major_axis': 6378249.2,
 'semi_minor_axis': 6356515.0}