diff --git a/com.ibm.wala.cast.python.test/data/np_shim.py b/com.ibm.wala.cast.python.test/data/np_shim.py
new file mode 100644
index 000000000..19fe7d8a3
--- /dev/null
+++ b/com.ibm.wala.cast.python.test/data/np_shim.py
@@ -0,0 +1 @@
+nan = -1
diff --git a/com.ibm.wala.cast.python.test/data/pandas_shim.py b/com.ibm.wala.cast.python.test/data/pandas_shim.py
new file mode 100644
index 000000000..8d9b53d57
--- /dev/null
+++ b/com.ibm.wala.cast.python.test/data/pandas_shim.py
@@ -0,0 +1,33 @@
+def isnull(x):
+    return False;
+
+class DataFrame():
+    def __init__(self, x):
+        self.x = x
+
+    def to_html(self, border=None):
+        return self.x
+
+class Series():
+    def __init__(self, x):
+        self.x = x
+        
+    def sum():
+        return 0
+
+class Categorical():
+    def __init__(self, x):
+        self.dtype = "type"
+        
+class DecimalArrayWithoutFromSequence():
+    def foo(self):
+        print('a')
+
+class DecimalArrayWithoutCoercion():
+    def foo(self):
+        print('b')
+
+class MultiIndex():
+    @staticmethod
+    def from_tuples(a, names):
+        return a