stashcp doesn't work with renamed destination file

[djw8605]

Error:

Traceback (most recent call last):
 File "/cvmfs/oasis.opensciencegrid.org/osg/modules/stashcp/4.0.1/bin/stashcp", line 353, in <module>
   main()
 File "/cvmfs/oasis.opensciencegrid.org/osg/modules/stashcp/4.0.1/bin/stashcp", line 347, in main
   doStashCpSingle(sourceFile=source, destination=destination, cache=cache, debug=args.debug)
 File "/cvmfs/oasis.opensciencegrid.org/osg/modules/stashcp/4.0.1/bin/stashcp", line 126, in doStashCpSingle
   payload['download_size']=dlSz
UnboundLocalError: local variable 'dlSz' referenced before assignment