code: def config(self, key, value=None, **kwargs):
          
          args = (key, value)
          return self._client.request('/config', args, decoder='json', **kwargs)
docs: Controls configuration variables.
  
          .. code-block:: python
  
              >>> c.config("Addresses.Gateway")
              {'Key': 'Addresses.Gateway', 'Value': '/ip4/127.0.0.1/tcp/8080'}
              >>> c.config("Addresses.Gateway", "/ip4/127.0.0.1/tcp/8081")
              {'Key': 'Addresses.Gateway', 'Value': '/ip4/127.0.0.1/tcp/8081'}
  
          Parameters
          ----------
          key : str
              The key of the configuration entry (e.g. "Addresses.API")
          value : dict
              The value to set the configuration entry to
  
          Returns
          -------
              dict : Requested/updated key and its (new) value