[Pulp-list] repo syncs failing on "cleaning duplicate packages"

[oogiejonz at yahoo.com]

All of our repos have started failing during sync when they get to "cleaning duplicate packages" stage.  No changes have been made to the server this is running on our to our pulp version.  We are running an older release, pulp-server-2.10.0-1.el6.noarch.
What we see when we try to sync:
# /usr/bin/pulp-admin rpm repo sync run --repo-id=rhel-6server+----------------------------------------------------------------------+                Synchronizing Repository [rhel-6server]+----------------------------------------------------------------------+
This command may be exited via ctrl+c without affecting the request.

Downloading metadata...[-]... completed
Downloading repository content...[-][==================================================] 100%RPMs:       0/0 itemsDelta RPMs: 0/0 items
... completed
Downloading distribution files...[==================================================] 100%Distributions: 0/0 items... completed
Importing errata...[|]... completed
Importing package groups/categories...[|]... completed
Cleaning duplicate packages...[|]
Task Failed
Importer indicated a failed response

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