Fix bug with pastes containing Unicode symbols failing to be uploaded.

pastes/models.py

@@ -137,7 +137,7 @@ def add_paste(text, user=None, title="Untitled", expiration=None, visibility=Non
 
         # Generate a random 8 character string for the char ID
         char_id = Paste.get_random_char_id()
-        hash = hashlib.sha256(text).hexdigest()
+        hash = hashlib.sha256(text.encode('utf-8')).hexdigest()
         submitted = datetime.datetime.now()
 
         # Make paste hidden if its visibility is hidden (private visibility may be added later)
@@ -185,7 +185,7 @@ def update_paste(id=None, char_id=None, text="", title="", visibility=None, form
         else:
             hidden = False
 
-        hash = hashlib.sha256(text).hexdigest()
+        hash = hashlib.sha256(text.encode('utf-8')).hexdigest()
 
         with transaction.atomic():
             # Save the new paste content both as raw text and with formatting
@@ -339,7 +339,7 @@ def add_paste_text(text, format=None):
         
         If format other than None is provided, Pygments will be used to highlight the text
         """
-        hash = hashlib.sha256(text).hexdigest()
+        hash = hashlib.sha256(text.encode('utf-8')).hexdigest()
 
         if format != None:
             text = highlighting.format_text(text, format)