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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def taskotron_changed_outcome(config, message):
 """ Taskotron task outcome changed With this rule, you can limit messages to only those task results with changed outcomes. This is useful when an object (a build, an update, etc) gets retested and either the object itself or the environment changes and the task outcome is now different (e.g. FAILED -> PASSED). """


    # We only operate on taskotron messages, first off.
    if not taskotron_result_new(config, message):
        return False

    outcome = message['msg']['result'].get('outcome')
    prev_outcome = message['msg']['result'].get('prev_outcome')

    return prev_outcome is not None and outcome != prev_outcome