code: def api_key(value=None):
          
  
          if value is None:
              return PyGraphistry._config['api_key']
  
          # setter
          if value is not PyGraphistry._config['api_key']:
              PyGraphistry._config['api_key'] = value.strip()
              PyGraphistry._is_authenticated = False
docs: Set or get the API key.
          Also set via environment variable GRAPHISTRY_API_KEY.