class_docstr: Test shared Alert class.
docstr: Alert Class - Alert Encoder - Invalid JSON raises parent exception
docstr_tok: ["Alert","Class","-","Alert","Encoder","-","Invalid","JSON","raises","parent","exception"]
code: def test_alert_encoder_invalid_json(self):
      """Alert Class - Alert Encoder - Invalid JSON raises parent exception"""
      assert_raises(TypeError, json.dumps, RuntimeWarning, default=list)
  
imports: import copy
  from datetime import datetime, timedelta
  import json
  from nose.tools import assert_equal, assert_false, assert_is_instance, assert_not_in, assert_raises, assert_true
  from streamalert.shared.alert import Alert, AlertCreationError
label_desc: Use image node_id 3 for calling the TestAlert obj's underlying member method code with example usage: obj.test_alert_encoder_invalid_json() without return types