old_contents: 
  import os
  
  from norc.settings import (NORC_LOG_DIR, BACKUP_SYSTEM,
      AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY, AWS_BUCKET_NAME)
  
  if BACKUP_SYSTEM == 'AmazonS3':
      from norc.norc_utils.aws import set_s3_key
  
  
  def s3_backup(fp, target):
      NUM_TRIES = 3
      for i in range(NUM_TRIES):
          try:
              set_s3_key(target, fp)
              return True
          except:
              if i == NUM_TRIES - 1:
                  raise
      return False
  
  BACKUP_SYSTEMS = {
      'AmazonS3': s3_backup,
  }
  
  def backup_log(rel_log_path):
      log_path = os.path.join(NORC_LOG_DIR, rel_log_path)
      log_file = open(log_path, 'rb')
      target = os.path.join('norc_logs/', rel_log_path)
      try:
          return _backup_file(log_file, target)
      finally:
          log_file.close()
  
  def _backup_file(fp, target):
      if BACKUP_SYSTEM:
          return BACKUP_SYSTEMS[BACKUP_SYSTEM](fp, target)
      else:
          return False
  
new_contents: 
  import os
  
  from norc.settings import NORC_LOG_DIR, BACKUP_SYSTEM
  
  if BACKUP_SYSTEM == 'AmazonS3':
      from norc.norc_utils.aws import set_s3_key
      from norc.settings import (AWS_ACCESS_KEY_ID,
          AWS_SECRET_ACCESS_KEY, AWS_BUCKET_NAME)
  
  
  def s3_backup(fp, target):
      NUM_TRIES = 3
      for i in range(NUM_TRIES):
          try:
              set_s3_key(target, fp)
              return True
          except:
              if i == NUM_TRIES - 1:
                  raise
      return False
  
  BACKUP_SYSTEMS = {
      'AmazonS3': s3_backup,
  }
  
  def backup_log(rel_log_path):
      log_path = os.path.join(NORC_LOG_DIR, rel_log_path)
      log_file = open(log_path, 'rb')
      target = os.path.join('norc_logs/', rel_log_path)
      try:
          return _backup_file(log_file, target)
      finally:
          log_file.close()
  
  def _backup_file(fp, target):
      if BACKUP_SYSTEM:
          return BACKUP_SYSTEMS[BACKUP_SYSTEM](fp, target)
      else:
          return False
  
subject: Move AWS_ setting imports under the check for AmazonS3 so Norc doesn't break without them.