updated graph_widgets.py

Author: yankev

plotly/widgets/graph_widget.py

@@ -9,14 +9,20 @@
 
 
 # TODO: protected imports?
-import ipywidgets as widgets
-from traitlets import Unicode
+import Ipython
 from IPython.display import Javascript, display
 
 import plotly.plotly.plotly as py
 from plotly import utils, tools
 from plotly.graph_objs import Figure
 
+if Ipython.version_info[0] > 3:
+    import ipywidgets as widgets
+    from traitlets import Unicode
+else:
+    import IPython.widgets as widgets
+    from IPython.trailets import Unicode
+
 # Load JS widget code
 # No officially recommended way to do this in any other way
 # http://mail.scipy.org/pipermail/ipython-dev/2014-April/013835.html