Update app.py

app.py

@@ -16,14 +16,13 @@ The following links are the detailed references:
 4. https://en.wikipedia.org/wiki/Dale%E2%80%93Chall_readability_formula
 """
 
-def measure_readability(message,history):    
-    response = urllib.request.urlopen(message)    
-    html = response.read().decode('utf8')
-    cleantext = BeautifulSoup(html).text
-    #cleantext = BeautifulSoup(html,'lxml').text    
-    text = re.sub(CLEANR,'', cleantext)
-   
-
+def measure_readability(message,history):
+    if "https://" in message:
+        response = urllib.request.urlopen(message)
+        html = response.read().decode('utf8')
+        cleantext = BeautifulSoup(html).text
+        #cleantext = BeautifulSoup(html,'lxml').text
+        text = re.sub(CLEANR,'', cleantext)
     vline1 = "==== Content Info ==== " + os.linesep
     vline2 = "Character Count "+str(textstat.char_count(text, ignore_spaces=True)) + os.linesep
     vline3 = "Lexicon Count "+str(textstat.lexicon_count(text, removepunct=True)) + os.linesep