Actually use 4-space indents in the PEP too.

pep-0007.txt

@@ -63,12 +63,12 @@ Code lay-out
 	static int
 	extra_ivars(PyTypeObject *type, PyTypeObject *base)
 	{
-		int t_size = PyType_BASICSIZE(type);
-		int b_size = PyType_BASICSIZE(base);
+	    int t_size = PyType_BASICSIZE(type);
+	    int b_size = PyType_BASICSIZE(base);
 
-		assert(t_size >= b_size); /* type smaller than base! */
-		...
-		return 1;
+	    assert(t_size >= b_size); /* type smaller than base! */
+	    ...
+	    return 1;
 	}
 
     - Code structure: one space between keywords like 'if', 'for' and
@@ -76,10 +76,10 @@ Code lay-out
       shown:
 
 	if (mro != NULL) {
-		...
+	    ...
 	}
 	else {
-		...
+	    ...
 	}
 
     - The return statement should *not* get redundant parentheses:
@@ -100,8 +100,8 @@ Code lay-out
       appropriately, e.g.:
 
 	PyErr_Format(PyExc_TypeError,
-		     "cannot create '%.100s' instances",
-		     type->tp_name);
+	             "cannot create '%.100s' instances",
+	             type->tp_name);
 
     - When you break a long expression at a binary operator, the
       operator goes at the end of the previous line, e.g.:
@@ -109,7 +109,7 @@ Code lay-out
 	if (type->tp_dictoffset != 0 && base->tp_dictoffset == 0 &&
 	    type->tp_dictoffset == b_size &&
 	    (size_t)t_size == b_size + sizeof(PyObject *))
-		return 0; /* "Forgive" adding a __dict__ only */
+	    return 0; /* "Forgive" adding a __dict__ only */
 
     - Put blank lines around functions, structure definitions, and
       major sections inside functions.