diff --git a/robustness/__init__.py b/robustness/__init__.py
index 78f22b6..1e9c668 100644
--- a/robustness/__init__.py
+++ b/robustness/__init__.py
@@ -1,2 +1,2 @@
 name = "robustness"
-__version__ = "1.0.post1"
+__version__ = "1.2.post1"
diff --git a/robustness/attack_steps.py b/robustness/attack_steps.py
index 61bd38a..f74b03d 100644
--- a/robustness/attack_steps.py
+++ b/robustness/attack_steps.py
@@ -122,7 +122,6 @@ def project(self, x):
     def step(self, x, g):
         """
         """
-        # Scale g so that each element of the batch is at least norm 1
         l = len(x.shape) - 1
         g_norm = ch.norm(g.view(g.shape[0], -1), dim=1).view(-1, *([1]*l))
         scaled_g = g / (g_norm + 1e-10)
diff --git a/robustness/datasets.py b/robustness/datasets.py
index bab1b88..e67bebe 100644
--- a/robustness/datasets.py
+++ b/robustness/datasets.py
@@ -88,7 +88,8 @@ def override_args(self, default_args, new_args):
         if len(extra_args) > 0: raise ValueError(f"Invalid arguments: {extra_args}")
         for k in kwargs:
             req_type = type(default_args[k])
-            if not isinstance(kwargs[k], req_type):
+            no_nones = (default_args[k] is not None) and (kwargs[k] is not None)
+            if no_nones and (not isinstance(kwargs[k], req_type)):
                 raise ValueError(f"Argument {k} should have type {req_type}")
         return {**default_args, **kwargs}
 
diff --git a/setup.py b/setup.py
index 677f14c..04de9d0 100644
--- a/setup.py
+++ b/setup.py
@@ -22,7 +22,7 @@
   # Versions should comply with PEP440.  For a discussion on single-sourcing
   # the version across setup.py and the project code, see
   # https://packaging.python.org/en/latest/single_source_version.html
-  version='1.2',
+  version='1.2.post1',
 
   description='Tools for Robustness',
   long_description=long_description,