planemo shed_update --check_diff --shed_target toolshed

Traceback (most recent call last):
  File "/usr/local/bin/planemo", line 11, in <module>
    sys.exit(planemo())
  File "/usr/local/lib/python2.7/dist-packages/click/core.py", line 664, in __call__
    return self.main(*args, **kwargs)
  File "/usr/local/lib/python2.7/dist-packages/click/core.py", line 644, in main
    rv = self.invoke(ctx)
  File "/usr/local/lib/python2.7/dist-packages/click/core.py", line 991, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/usr/local/lib/python2.7/dist-packages/click/core.py", line 837, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/usr/local/lib/python2.7/dist-packages/click/core.py", line 464, in invoke
    return callback(*args, **kwargs)
  File "/usr/local/lib/python2.7/dist-packages/click/decorators.py", line 64, in new_func
    return ctx.invoke(f, obj, *args[1:], **kwargs)
  File "/usr/local/lib/python2.7/dist-packages/click/core.py", line 464, in invoke
    return callback(*args, **kwargs)
  File "/usr/local/lib/python2.7/dist-packages/planemo/commands/cmd_shed_update.py", line 52, in cli
    tsi = shed.tool_shed_client(ctx, **kwds)
  File "/usr/local/lib/python2.7/dist-packages/planemo/shed/__init__.py", line 331, in tool_shed_client
    key = prop("key")
  File "/usr/local/lib/python2.7/dist-packages/planemo/shed/__init__.py", line 323, in prop
    return kwds.get("shed_%s" % key, None) or shed_config.get(key, None)
AttributeError: 'NoneType' object has no attribute 'get'