code: def add_layer(layer):
      """
      Add a layer
  
      :param layer: a BaseLayer object
      """
      _global_config.layers.append(layer)
  
imports: import base64
  import traceback
  import pyglet
  from geoplotlib.core import GeoplotlibApp
  from core import FONT_NAME
label_desc: Use image node_id 20 for calling a global function with example usage: add_layer(layer) without return types