#4000: fix several 2.x atavisms.

Doc/library/collections.rst

@@ -632,7 +632,7 @@ a fixed-width print format:
     ...     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.):
+    >>> for p in Point(3, 4), Point(14, 5/7):
     ...     print(p)
     Point: x= 3.000  y= 4.000  hypot= 5.000
     Point: x=14.000  y= 0.714  hypot=14.018

Doc/library/reprlib.rst

@@ -126,7 +126,7 @@ for file objects could be added::
            if obj.name in ['<stdin>', '<stdout>', '<stderr>']:
                return obj.name
            else:
-               return `obj`
+               return repr(obj)
 
    aRepr = MyRepr()
    print aRepr.repr(sys.stdin)          # prints '<stdin>'