Migrate tensorflow_graphics/io to Python 3.

PiperOrigin-RevId: 361944235

Author: tensorflower-gardener

tensorflow_graphics/io/exr.py

@@ -22,14 +22,16 @@
 import Imath
 import numpy as np
 import OpenEXR
+from six.moves import range
+from six.moves import zip
 
 
 _np_to_exr = {
     np.float16: Imath.PixelType.HALF,
     np.float32: Imath.PixelType.FLOAT,
     np.uint32: Imath.PixelType.UINT,
 }
-_exr_to_np = dict(zip(_np_to_exr.values(), _np_to_exr.keys()))
+_exr_to_np = dict(list(zip(list(_np_to_exr.values()), list(_np_to_exr.keys()))))
 
 
 def channels_to_ndarray(exr, channel_names):

tensorflow_graphics/io/tests/exr_test.py

@@ -15,6 +15,10 @@
 
 # pylint: disable=c-extension-no-member
 
+from __future__ import absolute_import
+from __future__ import division
+from __future__ import print_function
+
 import collections
 import tempfile
 
@@ -23,6 +27,7 @@
 import numpy as np
 import OpenEXR
 
+from six.moves import range
 from tensorflow_graphics.io import exr
 from tensorflow_graphics.util import test_case