How to create a dictionary with a dictionary inside and an array inside that dictionary?

Question

Python

Porting code from JavaScript to Python. I can't figure out how arrays work here.

Here is the simplified Python code:

mapdata = dict()
#Непонятно, какой определять массив, ведь в нём словарь, а в словаре массив.
mapdata['tiles'] = np.zeros((width,height), ???)

for x in range(0, width):
  for y in range(0, height):
    mapdata['tiles'][x][y] = dict()
    mapdata['tiles'][x][y]['coords'] = np.zeros((2,2), np.float32)
    mapdata['tiles'][x][y]['coords'][0] = массив с 2 элементами
    mapdata['tiles'][x][y]['coords'][1] = массив с 2 элементами

And here it is in JavaScript:

var mapdata = {
  tiles: []
};

for (var x = 0, x2 = txy[0][0]; x < tsize.width; x++, x2++) {
  mapdata.tiles[x] = [];

  for (var y = 0, y2 = txy[0][1]; y < tsize.height; y++, y2++) {
    mapdata.tiles[x][y] = {
      coords: [
        Bing.PixelXYToLatLong(x2 * 256, y2 * 256, level),// возвращает 2 элемента
        Bing.PixelXYToLatLong(x2 * 256 + 255, y2 * 256 + 255, level)// возвращает 2 элемента
      ]
    };
  }
}