Add power set challenge

recursion_dynamic/power_set/test_power_set.py

@@ -0,0 +1,39 @@
+from nose.tools import assert_equal
+
+
+class TestPowerSet(object):
+
+    def test_power_set(self):
+        input_set = ''
+        expected = ['']
+        self.run_test(input_set, expected)
+        input_set = 'a'
+        expected = ['a', '']
+        self.run_test(input_set, expected)
+        input_set = 'ab'
+        expected = ['a', 'ab', 'b', '']
+        self.run_test(input_set, expected)
+        input_set = 'abc'
+        expected = ['a', 'ab', 'abc', 'ac',
+                    'b', 'bc', 'c', '']
+        self.run_test(input_set, expected)
+        input_set = 'aabc'
+        expected = ['a', 'aa', 'aab', 'aabc', 
+                    'aac', 'ab', 'abc', 'ac', 
+                    'b', 'bc', 'c', '']
+        self.run_test(input_set, expected)
+        print('Success: test_power_set')
+
+    def run_test(self, input_set, expected):
+        combinatoric = Combinatoric()
+        result = combinatoric.find_power_set(input_set)
+        assert_equal(result, expected)
+
+
+def main():
+    test = TestPowerSet()
+    test.test_power_set()
+
+
+if __name__ == '__main__':
+    main()