title: Can't write text to grayscale PNG using PIL and python 2.7
body: <p>I am trying to write some text over a grayscale png using PIL and following this thread. It seems pretty straightforward but I am not sure what I am doing wrong.</p>
  
  <p><a href="https://stackoverflow.com/questions/16373425/add-text-on-image-using-pil">Add Text on Image using PIL</a></p>
  
  <p>Yet, when I try to do it dies on the <code>draw.text</code> function:</p>
  
  <pre><code>from PIL import Image, ImageDraw, ImageFont
  img = Image.open("test.png")
  draw = ImageDraw.Draw(img)
  font = ImageFont.truetype("open-sans/OpenSans-Regular.ttf", 8)
  # crashes on the line below:
  draw.text((0, 0), "Sample Text", (255, 255, 255), font=font)
  img.save('test_out.png')
  </code></pre>
  
  <p>This is the error log:</p>
  
  <pre><code>"C:\Python27\lib\site-packages\PIL\ImageDraw.py", line 109, in _getink
  ink = self.draw.draw_ink(ink, self.mode)
  TypeError: function takes exactly 1 argument (3 given)
  </code></pre>
  
  <p>Can anyone point me out the issue?</p>