Provide forward compatibility for IPossibleSite interface

src/OFS/interfaces.py

@@ -16,7 +16,6 @@
 from zope.container.interfaces import IContainer
 from zope.interface import Attribute
 from zope.interface import Interface
-from zope.location.interfaces import IPossibleSite
 from zope.location.interfaces import IRoot
 from zope.schema import Bool, BytesLine, Tuple
 
@@ -29,6 +28,12 @@ from persistent.interfaces import IPersistent
 from webdav.interfaces import IDAVCollection
 from webdav.interfaces import IDAVResource
 
+# BBB
+try:
+    from zope.component.interfaces import IPossibleSite
+except ImportError:
+    from zope.location.interfaces import IPossibleSite
+
 
 class IOrderedContainer(Interface):
 

src/Products/Five/component/__init__.py

@@ -18,7 +18,6 @@ import zope.interface
 import zope.component
 import zope.event
 from zope.component.interfaces import IComponentLookup
-from zope.location.interfaces import ISite, IPossibleSite
 from zope.traversing.interfaces import BeforeTraverseEvent
 
 import ExtensionClass
@@ -27,10 +26,20 @@ from Products.SiteAccess.AccessRule import AccessRule
 from ZPublisher.BeforeTraverse import registerBeforeTraverse
 from ZPublisher.BeforeTraverse import unregisterBeforeTraverse
 
+# BBB
+try:
+    from zope.component.interfaces import IPossibleSite
+    from zope.component.interfaces import ISite
+except ImportError:
+    from zope.location.interfaces import IPossibleSite
+    from zope.location.interfaces import ISite
+
+
 # Hook up custom component architecture calls
 from zope.site.hooks import setHooks
 setHooks()
 
+
 def findSite(obj, iface=ISite):
     """Find a site by walking up the object hierarchy, supporting both
     the ``ILocation`` API and Zope 2 Acquisition."""