Added utility function for calculating power set

monkey/common/utils/itertools_extensions.py

@@ -0,0 +1,9 @@
+from itertools import chain, combinations
+
+
+def power_set(iterable):
+    """
+    https://docs.python.org/3/library/itertools.html#itertools-recipes
+    """
+    s = list(iterable)
+    return chain.from_iterable(combinations(s, r) for r in range(1, len(s) + 1))

monkey/common/utils/test_power_set.py

@@ -0,0 +1,18 @@
+from unittest import TestCase
+
+
+class TestPower_set(TestCase):
+    def test_power_set(self):
+        before = ('a', 'b', 'c')
+        after_expected = [
+            ('a', ),
+            ('b',),
+            ('c',),
+            ('a', 'b'),
+            ('a', 'c'),
+            ('b', 'c'),
+            ('a', 'b', 'c'),
+        ]
+
+        from common.utils.itertools_extensions import power_set
+        self.assertEquals(list(power_set(before)), after_expected)