Type(allow_none=True)

IPython/kernel/inprocess/ipkernel.py

@@ -46,7 +46,7 b' class InProcessKernel(IPythonKernel):'
     # Kernel interface
     #-------------------------------------------------------------------------
 
-    shell_class = Type()
+    shell_class = Type(allow_none=True)
     shell_streams = List()
     control_stream = Any()
     iopub_socket = Instance(DummySocket, ())

IPython/kernel/manager.py

@@ -49,7 +49,7 b' class KernelManager(ConnectionFileMixin):'
 
     # the class to create with our `client` method
     client_class = DottedObjectName('IPython.kernel.blocking.BlockingKernelClient')
-    client_factory = Type()
+    client_factory = Type(allow_none=True)
     def _client_class_changed(self, name, old, new):
         self.client_factory = import_item(str(new))
 

ipython_parallel/client/view.py

@@ -603,7 +603,7 b' class DirectView(View):'
 
 
         If block=False
-          An :class:`~IPython.parallel.client.asyncresult.AsyncMapResult` instance.
+          An :class:`~ipython_parallel.client.asyncresult.AsyncMapResult` instance.
           An object like AsyncResult, but which reassembles the sequence of results
           into a single list. AsyncMapResults can be iterated through before all
           results are complete.

ipython_parallel/controller/scheduler.py

@@ -180,7 +180,7 b' help="""select the task scheduler scheme [default: Python LRU]'
         self.scheme = globals()[new]
 
     # input arguments:
-    scheme = Instance(FunctionType, allow_none=True) # function for determining the destination
+    scheme = Instance(FunctionType) # function for determining the destination
     def _scheme_default(self):
         return leastload
     client_stream = Instance(zmqstream.ZMQStream, allow_none=True) # client-facing stream
@@ -190,7 +190,7 b' help="""select the task scheduler scheme [default: Python LRU]'
     query_stream = Instance(zmqstream.ZMQStream, allow_none=True) # hub-facing DEALER stream
 
     # internals:
-    queue = Instance(deque, allow_none=True) # sorted list of Jobs
+    queue = Instance(deque) # sorted list of Jobs
     def _queue_default(self):
         return deque()
     queue_map = Dict() # dict by msg_id of Jobs (for O(1) access to the Queue)

jupyter_nbformat/sign.py

@@ -87,7 +87,7 b' def signature_removed(nb):'
 class NotebookNotary(LoggingConfigurable):
     """A class for computing and verifying notebook signatures."""
     
-    profile_dir = Instance("IPython.core.profiledir.ProfileDir", allow_none=True)
+    profile_dir = Instance("IPython.core.profiledir.ProfileDir")
     def _profile_dir_default(self):
         from IPython.core.application import BaseIPythonApplication
         app = None
@@ -388,7 +388,7 b' class TrustNotebookApp(BaseIPythonApplication):'
         """
     )
     
-    notary = Instance(NotebookNotary, allow_none=True)
+    notary = Instance(NotebookNotary)
     def _notary_default(self):
         return NotebookNotary(parent=self, profile_dir=self.profile_dir)