diff --git a/Lib/python/pycontainer.swg b/Lib/python/pycontainer.swg
index dcada87c7..425cc45fc 100644
--- a/Lib/python/pycontainer.swg
+++ b/Lib/python/pycontainer.swg
@@ -710,7 +710,8 @@ namespace swig
 #if defined(SWIGPYTHON_BUILTIN)
   %feature("python:slot", "tp_iter", functype="getiterfunc") iterator;
 #else
-  %pythoncode {def __iter__(self): return self.iterator()}
+  %pythoncode {def __iter__(self):
+    return self.iterator()}
 #endif
   }
 
diff --git a/Lib/python/std_map.i b/Lib/python/std_map.i
index 66ed68da5..58902bca4 100644
--- a/Lib/python/std_map.i
+++ b/Lib/python/std_map.i
@@ -176,10 +176,14 @@
 
 #else
   %extend {
-    %pythoncode {def __iter__(self): return self.key_iterator()}    
-    %pythoncode {def iterkeys(self): return self.key_iterator()}
-    %pythoncode {def itervalues(self): return self.value_iterator()}
-    %pythoncode {def iteritems(self): return self.iterator()}
+    %pythoncode {def __iter__(self):
+    return self.key_iterator()}    
+    %pythoncode {def iterkeys(self):
+    return self.key_iterator()}
+    %pythoncode {def itervalues(self):
+    return self.value_iterator()}
+    %pythoncode {def iteritems(self):
+    return self.iterator()}
   }
 #endif
 
diff --git a/Lib/python/std_unordered_map.i b/Lib/python/std_unordered_map.i
index b456035e2..737468234 100644
--- a/Lib/python/std_unordered_map.i
+++ b/Lib/python/std_unordered_map.i
@@ -231,10 +231,14 @@
       return swig::make_output_value_iterator(self->begin(), self->begin(), self->end(), *PYTHON_SELF);
     }
 
-    %pythoncode {def __iter__(self): return self.key_iterator()}    
-    %pythoncode {def iterkeys(self): return self.key_iterator()}
-    %pythoncode {def itervalues(self): return self.value_iterator()}
-    %pythoncode {def iteritems(self): return self.iterator()}
+    %pythoncode {def __iter__(self):
+    return self.key_iterator()}    
+    %pythoncode {def iterkeys(self):
+    return self.key_iterator()}
+    %pythoncode {def itervalues(self):
+    return self.value_iterator()}
+    %pythoncode {def iteritems(self):
+    return self.iterator()}
   }
 %enddef