You continue to use the existing GData API according to the @froggythefrog page:
I see that many GData APIs are outdated and newer versions are no longer based on it, but it says that the Google Site Data API is not changing, in particular "the GData version is still online."
This may mean that the days can be numbered, but at the moment this is the current API.
I see no mention of the fact that the GData API as a whole is completely out of date.
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