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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 handler(event, context):
 # pylint: disable=W0613 """ Historical S3 event collector. This collector is responsible for processing CloudWatch events and polling events. """

    records = deserialize_records(event['Records'])

    # Split records into two groups, update and delete.
    # We don't want to query for deleted records.
    update_records, delete_records = group_records_by_type(records, UPDATE_EVENTS)

    LOG.debug('[@] Processing update records...')
    process_update_records(update_records)
    LOG.debug('[@] Completed processing of update records.')

    LOG.debug('[@] Processing delete records...')
    process_delete_records(delete_records)
    LOG.debug('[@] Completed processing of delete records.')

    LOG.debug('[@] Successfully updated current Historical table')