added more examples for java and python

Author: nikololiahim

sandbox_java/Simple.java

@@ -0,0 +1,2 @@
+class c {}
+class d extends c {}

sandbox_python/class_examples.py

@@ -0,0 +1,2 @@
+class c: pass
+class d(c): pass

sandbox_python/mutualrec.py

@@ -0,0 +1,8 @@
+class c:
+    def f(self, x): 
+        return x
+    def g(self, x):
+        return self.f(x)
+class d(c):
+    def f(self, x):
+        return self.g(x)