private static Dictionary<PythonLanguageVersion, Tokenizer> _tokenizers; // tokenizer for each version, shared between all buffers
internal PythonClassifier(PythonClassifierProvider provider, ITextBuffer buffer) {
buffer.Changed += BufferChanged;
buffer.ContentTypeChanged += BufferContentTypeChanged;
_tokenCache = new TokenCache();
_provider = provider;
_buffer = buffer;
var analyzer = _buffer.GetAnalyzer(provider._serviceProvider);
Debug.Assert(analyzer != null);
_version = analyzer.InterpreterFactory.GetLanguageVersion();
}