FIX: Specify field index for Python 2.6 compatible use of str.format()

skimage/novice/_novice.py

@@ -25,7 +25,7 @@ def open(path):
 def _verify_picture_index(index):
     """Raise error if picture index is not a 2D index/slice."""
     if not (isinstance(index, tuple) and len(index) == 2):
-        raise IndexError("Expected 2D index but got {!r}".format(index))
+        raise IndexError("Expected 2D index but got {0!r}".format(index))
 
     if all(isinstance(i, int) for i in index):
         return index

skimage/novice/tests/test_novice.py

@@ -268,5 +268,4 @@ def test_pixel_blue_raises():
 
 
 if __name__ == '__main__':
-    from numpy import testing
-    testing.run_module_suite()
+    np.testing.run_module_suite()