Remove main section that was only used during testing and development

Lib/collections/__main__.py

-################################################################################
-### 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)))