move @annotate to py3compat

IPython/html/widgets/__init__.py

@@ -9,4 +9,4 b' from .widget_int import IntTextWidget, BoundedIntTextWidget, IntSliderWidget, In'
 from .widget_selection import RadioButtonsWidget, ToggleButtonsWidget, DropdownWidget, SelectWidget
 from .widget_selectioncontainer import TabWidget, AccordionWidget
 from .widget_string import HTMLWidget, LatexWidget, TextWidget, TextareaWidget
-from .interaction import interact, interactive, annotate, const
+from .interaction import interact, interactive, const

IPython/html/widgets/interaction.py

@@ -246,17 +246,3 b' class const(HasTraits):'
     description = Unicode('', help="Any Python object")
     def __init__(self, value, **kwargs):
         super(const, self).__init__(value=value, **kwargs)
-
-def annotate(**kwargs):
-    """Python 3 compatible function annotation for Python 2."""
-    if not kwargs:
-        raise ValueError('annotations must be provided as keyword arguments')
-    def dec(f):
-        if hasattr(f, '__annotations__'):
-            for k, v in kwargs.items():
-                f.__annotations__[k] = v
-        else:
-            f.__annotations__ = kwargs
-        return f
-    return dec
-

IPython/utils/py3compat.py

@@ -223,6 +223,21 b' else:'
                 filename = fname
             builtin_mod.execfile(filename, *where)
 
+
+def annotate(**kwargs):
+    """Python 3 compatible function annotation for Python 2."""
+    if not kwargs:
+        raise ValueError('annotations must be provided as keyword arguments')
+    def dec(f):
+        if hasattr(f, '__annotations__'):
+            for k, v in kwargs.items():
+                f.__annotations__[k] = v
+        else:
+            f.__annotations__ = kwargs
+        return f
+    return dec
+
+
 # Parts below taken from six:
 # Copyright (c) 2010-2013 Benjamin Peterson
 #