code: def logout(client):
      
      if not client.session_id:
          client.request_session()
  
      concierge_request_header = client.construct_concierge_header(
          url=("http://membersuite.com/contracts/IConciergeAPIService/"
               "Logout"))
  
      logout_result = client.client.service.Logout(
          _soapheaders=[concierge_request_header])
  
      result = logout_result["body"]["LogoutResult"]
  
      if result["SessionID"] is None:  # Success!
          client.session_id = None
      else:  # Failure . . .
          raise LogoutError(result=result)
docs: Log out the currently logged-in user.
  
      There's a really crappy side-effect here - the session_id
      attribute of the `client` passed in will be reset to None if the
      logout succeeds, which is going to be almost always, let's hope.