$ s3cmd ls s3://ka-mapreduce/entity_store/ProblemLog/

    An unexpected error has occurred.
  Please report the following lines to:

Problem: IndexError: list index out of range

Traceback (most recent call last):
  File "/usr/bin/s3cmd", line 1736, in <module>
  File "/usr/bin/s3cmd", line 1681, in main
  File "/usr/bin/s3cmd", line 89, in cmd_ls
    subcmd_bucket_list(s3, uri)
  File "/usr/bin/s3cmd", line 119, in subcmd_bucket_list
    response = s3.bucket_list(bucket, prefix = prefix)
  File "/usr/share/s3cmd/S3/S3.py", line 181, in bucket_list
    uri_params['marker'] = self.urlencode_string(list[-1]["Key"])
IndexError: list index out of range