1 files changed, 38 insertions, 0 deletions
diff --git a/Lib/collections/__main__.py b/Lib/collections/__main__.py
new file mode 100644
index 0000000000..763e38e0c4
--- /dev/null
+++ b/Lib/collections/__main__.py
@@ -0,0 +1,38 @@
+################################################################################
+### Simple tests
+################################################################################
+
+# verify that instances can be pickled
+from collections import namedtuple
+from pickle import loads, dumps
+Point = namedtuple('Point', 'x, y', True)
+p = Point(x=10, y=20)
+assert p == loads(dumps(p))
+
+# test and demonstrate ability to override methods
+class Point(namedtuple('Point', 'x y')):
+    __slots__ = ()
+    @property
+    def hypot(self):
+        return (self.x ** 2 + self.y ** 2) ** 0.5
+    def __str__(self):
+        return 'Point: x=%6.3f  y=%6.3f  hypot=%6.3f' % (self.x, self.y, self.hypot)
+
+for p in Point(3, 4), Point(14, 5/7.):
+    print (p)
+
+class Point(namedtuple('Point', 'x y')):
+    'Point class with optimized _make() and _replace() without error-checking'
+    __slots__ = ()
+    _make = classmethod(tuple.__new__)
+    def _replace(self, _map=map, **kwds):
+        return self._make(_map(kwds.get, ('x', 'y'), self))
+
+print(Point(11, 22)._replace(x=100))
+
+Point3D = namedtuple('Point3D', Point._fields + ('z',))
+print(Point3D.__doc__)
+
+import doctest, collections
+TestResults = namedtuple('TestResults', 'failed attempted')
+print(TestResults(*doctest.testmod(collections)))