1 files changed, 43 insertions, 0 deletions
diff --git a/obnamlib/fmt_ga/leaf.py b/obnamlib/fmt_ga/leaf.py
new file mode 100644
index 00000000..6522a6a9
--- /dev/null
+++ b/obnamlib/fmt_ga/leaf.py
@@ -0,0 +1,43 @@
+# Copyright 2016  Lars Wirzenius
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+# =*= License: GPL-3+ =*=
+
+
+import copy
+
+
+class CowLeaf(object):
+
+    def __init__(self):
+        self._dict = {}
+
+    def __len__(self):
+        return len(self._dict)
+
+    def keys(self):
+        return self._dict.keys()
+
+    def lookup(self, key):
+        return self._dict.get(key, None)
+
+    def insert(self, key, value):
+        self._dict[key] = value
+
+    def as_dict(self):
+        return copy.deepcopy(self._dict)
+
+    def from_dict(self, a_dict):
+        self._dict = a_dict