Populated dictionary as default argument for __init__

I would like my class to have a set of default settings, here is my attempt:

import requests

defaultConfig = {
  'endpoint': 'http://localhost:4333/api/data'
}

class DataRenderer:
  def __init__(self, config = defaultConfig):
    self.config = config
  def drawGraph(self, options):
    retu requests.post(self.config.endpoint, json = {
      data: {
        'action': 'drawGraph',
        'graph': options
      }
    })

I get a AttributeError: 'dict' object has no attribute 'endpoint' error. It picks up that it's a dictionary object, but oddly the attributes don't seem to be initialized yet? Is there a better way to achieve the same thing (without inlining the whole dictionary in the args)