diff --git a/Circle.py b/Circle.py
new file mode 100644
index 0000000..f0c33d1
--- /dev/null
+++ b/Circle.py
@@ -0,0 +1,3 @@
+
+class Circle(Shape):
+    pass
diff --git a/Line.py b/Line.py
new file mode 100644
index 0000000..a77ebef
--- /dev/null
+++ b/Line.py
@@ -0,0 +1,3 @@
+
+class Line(Shape):
+    pass
diff --git a/Shape.py b/Shape.py
new file mode 100644
index 0000000..518346a
--- /dev/null
+++ b/Shape.py
@@ -0,0 +1,3 @@
+
+class Shape(object):
+    pass
diff --git a/Sketch.py b/Sketch.py
new file mode 100644
index 0000000..5a83494
--- /dev/null
+++ b/Sketch.py
@@ -0,0 +1,10 @@
+
+class Sketch(object):
+    def __init__(self):
+        self.shapes = []
+
+    def __iter__(self):
+        return self.shapes.__iter__()
+
+    def __contains__(self, item):
+        return self.shapes.__contains__(item)
diff --git a/Window.py b/Window.py
index e25c853..7df1cce 100644
--- a/Window.py
+++ b/Window.py
@@ -4,6 +4,8 @@ import gtk.gtkgl
 
 from OpenGL.GL import *
 
+from Sketch import Sketch
+
 class Window:
     def __init__(self, title):
         self.window = gtk.Window(gtk.WINDOW_TOPLEVEL)