class_docstr: Test shared Alert class.
docstr: Alert Class - Compute Diff - Difference in Nested Dictionary
docstr_tok: ["Alert","Class","-","Compute","Diff","-","Difference","in","Nested","Dictionary"]
code: def test_compute_diff_nested(self):
      """Alert Class - Compute Diff - Difference in Nested Dictionary"""
      # This is the example given in the docstring
      common = {"abc": 123, "nested": {"A": 1}}
      record = {"abc": 123, "nested": {"A": 1, "B": 2}}
      assert_equal(
          {"nested": {"B": 2}}, Alert._compute_diff(common, record)
      )
  
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 34 for calling the TestAlert obj's underlying member method code with example usage: obj.test_compute_diff_nested() without return types