gnu: Add python-atomicwrites.

* gnu/packages/python.scm (python-atomicwrites): New variable.

gnu/packages/python.scm

@@ -6706,3 +6706,20 @@ WebSocket usage in Python programs.")
 
 (define-public python2-websocket-client
   (package-with-python2 python-websocket-client))
+
+(define-public python-atomicwrites
+  (package
+    (name "python-atomicwrites")
+    (version "0.1.8")
+    (source (origin
+             (method url-fetch)
+             (uri (pypi-uri "atomicwrites" version))
+             (sha256
+              (base32
+               "13nwk0gw0yb61pnf5vxs3fvhav6q3zrf08x9ggc93bnk5fsssx1j"))))
+    (build-system python-build-system)
+    (synopsis "Atomic file writes in Python")
+    (description "Library for atomic file writes using platform dependent tools
+for atomic filesystem operations.")
+    (home-page "https://github.com/untitaker/python-atomicwrites")
+    (license license:expat)))