Chameleon fault tolerance

Change-Id: Id7060f121f85a444005dfeff6279daef51a59295
diff --git a/chameleon/asleep.py b/chameleon/asleep.py
new file mode 100644
index 0000000..e1868ab
--- /dev/null
+++ b/chameleon/asleep.py
@@ -0,0 +1,27 @@
+#
+# Copyright 2016 the original author or authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+""" Async sleep (asleep) method and other twisted goodies """
+
+from twisted.internet import reactor
+from twisted.internet.defer import Deferred
+
+
+def asleep(dt):
+    assert isinstance(dt, (int, float))
+    d = Deferred()
+    reactor.callLater(dt, lambda: d.callback(None))
+    return d