class_docstr: Test shared Alert class.
docstr: Alert Class - Compute Common - Empty Common Set
docstr_tok: ["Alert","Class","-","Compute","Common","-","Empty","Common","Set"]
code: def test_compute_common_no_similarities(self):
      """Alert Class - Compute Common - Empty Common Set"""
      record1 = {"a": -1, "b": -2, "c": -3, "d": {"e": 0}}
      record2 = {"a": 1, "b": 2, "c": 3}
      assert_equal({}, Alert._compute_common([record1, record2]))
  
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 25 for calling the TestAlert obj's underlying member method code with example usage: obj.test_compute_common_no_similarities() without return types