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This is probably the answer to my previous question: List Elements or Datasets of a given Layer.

The version of arcpy that I am using does not include GetNAClassNames

naClasses =

AttributeError: 'module' object has no attribute 'GetClassNames'

According to this help topic, GetNAClassNames is in ArcGIS 10.1. Why is it not in my version?

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What version of ESRI products are you using? Some companies/organizations are behind because of testing and licensing requirements. – mhoran_psprep Jul 2 '12 at 3:19
You're not on 10.1, plain and simple. It's only been out for a couple of weeks. – Jason Scheirer Jul 2 '12 at 3:41
You are right. I checked my version and it is 10.0.2414. But now, there is no way for me to get that ClassNames of the service area layers?? I need to select the Polygons (layer) which is inside the Service Area layer. – Janz Jul 2 '12 at 5:37

If your company is current on esri maintenance, 10.1 is available for download. The license manager will have to be updated, not a difficult task. The install is straight forward. Our only issue so far is ArcINFO Workstation 9.0 no longer talks with a 10.1 LM.

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Caution: some companies/organizations restrict your ability to install or upgrade software. You may need to make a request to your IT help desk. – mhoran_psprep Jul 2 '12 at 12:46

From what you have shown us of your code and error there seems to be a mismatch.

You are trying to call and yet the error says:

AttributeError: 'module' object has no attribute 'GetClassNames'

and not:

AttributeError: 'module' object has no attribute 'GetNAClassNames'

I think you are either looking at a line of code that is not responsible for the error, and recommend that you check/present the precise code snippet that produces your error.

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