title: Image.save() - FileNotFoundError
body: <p>I just have kind of toolbar. It allows you to take screenshots with one button:</p>
  
  <pre><code>def screenshot():
      try:
          os.mkdir(r"C:\Screenshots")
      except FileExistsError:
          pass
  
      global img
      img = ImageGrab.grab()
      global today
      today = time.strftime("%d_%B_%Y__%H_%m_%S")
      saveas=os.path.join(SaveDirectory, "Screenshot_" + today + ".jpg")
      img.save(saveas)
      bubble = Thread(target = balloon_tip, args = ("Saved!", "Screenshot was saved at C:\Screenshots"))
      bubble.start()
  </code></pre>
  
  <p>However I get this Error:</p>
  
  <pre><code>    Exception in thread Thread-1:
  Traceback (most recent call last):
    File "C:\Python3.6\lib\threading.py", line 916, in _bootstrap_inner
      self.run()
    File "C:\Python3.6\lib\threading.py", line 864, in run
      self._target(*self._args, **self._kwargs)
    File "C:\Users\mbilal25tr\Desktop\Python Projects\Toolbar py\toolbar.pyw", line 140, in screenshot
      img.save(saveas)
    File "C:\Python3.6\lib\site-packages\PIL\Image.py", line 1725, in save
      fp = builtins.open(filename, "w+b")
  FileNotFoundError: [Errno 2] No such file or directory: 'C:\\Screenshot\\Screenshot_29_March_2017__19_03_01.jpg'
  </code></pre>
  
  <p>But I don't get it! Isn't <code>img.save()</code> supposed to create an image file? Why does it try o open it before creating? How should I expect it to find it and run without an error?!</p>
  
  <p>Thanks...</p>