update python-hand-text.md

update while condition to avoid infinite loop when retrieving the recognized text returns back {'status': 'NotStarted'}

During the Polling, the API returns back 
{'status': 'NotStarted'}
{'status': 'Running'}
then if any error happens inside the API, the API returns back 
{'status': 'Failed'}
otherwise the API returns back 
{'recognitionResult': {'lines': [...]}, 'status': 'Succeeded'}

Author: Azadehkhojandi

articles/cognitive-services/Computer-vision/QuickStarts/python-hand-text.md

@@ -75,15 +75,21 @@ operation_url = response.headers["Operation-Location"]
 # The recognized text isn't immediately available, so poll to wait for completion.
 import time
 analysis = {}
-while "recognitionResult" not in analysis:
+poll = True
+while (poll):
     response_final = requests.get(
         response.headers["Operation-Location"], headers=headers)
     analysis = response_final.json()
-    time.sleep(1)
+    if ("recognitionResult" in analysis):
+        poll= False 
+    if ("status" in analysis and analysis['status'] == 'Failed'):
+        poll= False
 
-# Extract the recognized text, with bounding boxes.
-polygons = [(line["boundingBox"], line["text"])
-    for line in analysis["recognitionResult"]["lines"]]
+polygons=[]
+if ("recognitionResult" in analysis):
+    # Extract the recognized text, with bounding boxes.
+    polygons = [(line["boundingBox"], line["text"])
+        for line in analysis["recognitionResult"]["lines"]]
 
 # Display the image and overlay it with the extracted text.
 from matplotlib.patches import Polygon