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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 _cleaned(_pipeline_objects):
 """Return standardized pipeline objects to be used for comparing Remove year, month, and day components of the startDateTime so that data pipelines with the same time of day but different days are considered equal. """

    pipeline_objects = copy.deepcopy(_pipeline_objects)
    for pipeline_object in pipeline_objects:
        if pipeline_object['id'] == 'DefaultSchedule':
            for field_object in pipeline_object['fields']:
                if field_object['key'] == 'startDateTime':
                    start_date_time_string = field_object['stringValue']
                    start_date_time = datetime.datetime.strptime(start_date_time_string,
                                                                 "%Y-%m-%dT%H:%M:%S")
                    field_object['stringValue'] = start_date_time.strftime("%H:%M:%S")
    return pipeline_objects