Added printing requirements

zope/interface/tests/__init__.py

@@ -0,0 +1,13 @@
+import os
+import unittest
+
+def additional_tests():
+    suites = unittest.TestSuite()
+    for file in os.listdir(os.path.dirname(__file__)):
+        if file.endswith('.py') and file!='__init__.py':
+            name = os.path.splitext(file)[0]
+            module = __import__('.'.join((__name__, name)), globals(), 
+                                locals(), [name])
+            if hasattr(module, 'test_suite'):
+                suites.addTests(module.test_suite())
+    return suites