Reduce doctest precision

src/doc/en/thematic_tutorials/tutorial-programming-python.rst

@@ -799,6 +799,7 @@ below::
     [(1, 2, 3), 'newvalue', 14, 'newervalue']
     sage: set(d.values()) == set([14, (1, 2, 3), 'newvalue', 'newervalue'])
     True
+
 ::
 
     sage: d.items()    # random order

src/sage/graphs/generic_graph.py

@@ -14748,11 +14748,11 @@ def layout(self, layout = None, pos = None, dim = 2, save_pos = False, **options
              ('1', 0): [1.12..., -0.830...],
              ('1', 1): [2.50..., -0.545...]}
 
-            sage: g.layout(layout = "acyclic_dummy", save_pos = True)
-            {('0', 0): [0.33..., 0],
-             ('0', 1): [0.33..., 1],
-             ('1', 0): [0.67..., 0],
-             ('1', 1): [0.67..., 1]}
+            sage: g.layout(layout="acyclic_dummy", save_pos=True)
+            {('0', 0): [0.3..., 0],
+             ('0', 1): [0.3..., 1],
+             ('1', 0): [0.6..., 0],
+             ('1', 1): [0.6..., 1]}
 
             sage: g.layout(dim = 3)
             {('0', 0): [2.02..., 0.528..., 0.343...],