Fix for NLTK related import failure (#1487)

Signed-off-by: okhleif-IL <omar.khleif@intel.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Author: okhleif-IL

DocSum/ui/gradio/docsum_ui_gradio.py

@@ -313,11 +313,17 @@ def render(self):
 if __name__ == "__main__":
     import argparse
 
+    import nltk
+
     parser = argparse.ArgumentParser()
     parser.add_argument("--host", type=str, default="0.0.0.0")
     parser.add_argument("--port", type=int, default=5173)
 
     args = parser.parse_args()
     logger.info(">>> Starting server at %s:%d", args.host, args.port)
 
+    # Needed for UnstructuredURLLoader when reading content from a URL
+    nltk.download("punkt_tab")
+    nltk.download("averaged_perceptron_tagger_eng")
+
     uvicorn.run(app, host=args.host, port=args.port)