diff --git a/MANIFEST.in b/MANIFEST.in
index c28ab72..af97cc8 100644
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -1,2 +1,2 @@
-include README.md
+include README.rst
 include LICENSE.md
diff --git a/nest/nest.py b/nest/nest.py
index da80500..05f5f8f 100644
--- a/nest/nest.py
+++ b/nest/nest.py
@@ -156,7 +156,7 @@ def _cache(self):
 
     def _callback(self, res):
         if self.auth_callback is not None and isinstance(self.auth_callback,
-                                                         collections.Callable):
+                                                         collections.abc.Callable):
             self.auth_callback(res)
 
     def login(self, headers=None):
diff --git a/setup.py b/setup.py
index 7771327..5ad75cc 100755
--- a/setup.py
+++ b/setup.py
@@ -11,7 +11,7 @@
 #                Bumping Minor means API bugfix or new functionality.
 #                Bumping Micro means CLI change of any kind unless it is
 #                    significant enough to warrant a minor/major bump.
-version = '4.1.0'
+version = '4.2.0'
 
 
 setup(name='python-nest',