diff --git a/src/Gui/Selection.cpp b/src/Gui/Selection.cpp
index 56bd3edba7..06d94a1793 100644
--- a/src/Gui/Selection.cpp
+++ b/src/Gui/Selection.cpp
@@ -1756,7 +1756,7 @@ PyMethodDef SelectionSingleton::Methods[] = {
     {"removeSelection",      (PyCFunction) SelectionSingleton::sRemoveSelection, METH_VARARGS,
      "removeSelection(object) -- Remove an object from the selection"},
     {"clearSelection"  ,     (PyCFunction) SelectionSingleton::sClearSelection, METH_VARARGS,
-     "clearSelection(doc=None,clearPreSelect=True) -- Clear the selection\n"
+     "clearSelection(docName='',clearPreSelect=True) -- Clear the selection\n"
      "Clear the selection to the given document name. If no document is\n"
      "given the complete selection is cleared."},
     {"isSelected",           (PyCFunction) SelectionSingleton::sIsSelected, METH_VARARGS,
@@ -1773,21 +1773,21 @@ PyMethodDef SelectionSingleton::Methods[] = {
      "second argumeht defines the document name. If no document name is given the\n"
      "currently active document is used"},
     {"getSelection",         (PyCFunction) SelectionSingleton::sGetSelection, METH_VARARGS,
-     "getSelection(docName=None,resolve=1,single=False) -- Return a list of selected objects\n"
-     "\ndocName - document name. None means the active document, and '*' means all document"
+     "getSelection(docName='',resolve=1,single=False) -- Return a list of selected objects\n"
+     "\ndocName - document name. Empty string means the active document, and '*' means all document"
      "\nresolve - whether to resolve the subname references."
      "\n          0: do not resolve, 1: resolve, 2: resolve with element map"
      "\nsingle - only return if there is only one selection"},
     {"getPickedList",         (PyCFunction) SelectionSingleton::sGetPickedList, 1,
-     "getPickedList(docName=None) -- Return a list of objects under the last mouse click\n"
-     "\ndocName - document name. None means the active document, and '*' means all document"},
+     "getPickedList(docName='') -- Return a list of objects under the last mouse click\n"
+     "\ndocName - document name. Empty string means the active document, and '*' means all document"},
     {"enablePickedList",      (PyCFunction) SelectionSingleton::sEnablePickedList, METH_VARARGS,
      "enablePickedList(boolean) -- Enable/disable pick list"},
     {"getCompleteSelection", (PyCFunction) SelectionSingleton::sGetCompleteSelection, METH_VARARGS,
      "getCompleteSelection(resolve=1) -- Return a list of selected objects of all documents."},
     {"getSelectionEx",         (PyCFunction) SelectionSingleton::sGetSelectionEx, METH_VARARGS,
-     "getSelectionEx(docName=None,resolve=1, single=False) -- Return a list of SelectionObjects\n"
-     "\ndocName - document name. None means the active document, and '*' means all document"
+     "getSelectionEx(docName='',resolve=1, single=False) -- Return a list of SelectionObjects\n"
+     "\ndocName - document name. Empty string means the active document, and '*' means all document"
      "\nresolve - whether to resolve the subname references."
      "\n          0: do not resolve, 1: resolve, 2: resolve with element map"
      "\nsingle - only return if there is only one selection\n"
@@ -1826,12 +1826,12 @@ PyMethodDef SelectionSingleton::Methods[] = {
      "clearForward: whether to clear the forward selection stack.\n"
      "overwrite: overwrite the top back selection stack with current selection."},
     {"hasSelection",      (PyCFunction) SelectionSingleton::sHasSelection, METH_VARARGS,
-     "hasSelection(docName=None, resolve=False) -- check if there is any selection\n"},
+     "hasSelection(docName='', resolve=False) -- check if there is any selection\n"},
     {"hasSubSelection",   (PyCFunction) SelectionSingleton::sHasSubSelection, METH_VARARGS,
-     "hasSubSelection(docName=None,subElement=False) -- check if there is any selection with subname\n"},
+     "hasSubSelection(docName='',subElement=False) -- check if there is any selection with subname\n"},
     {"getSelectionFromStack",(PyCFunction) SelectionSingleton::sGetSelectionFromStack, METH_VARARGS,
-     "getSelectionFromStack(docName=None,resolve=1,index=0) -- Return a list of SelectionObjects from selection stack\n"
-     "\ndocName - document name. None means the active document, and '*' means all document"
+     "getSelectionFromStack(docName='',resolve=1,index=0) -- Return a list of SelectionObjects from selection stack\n"
+     "\ndocName - document name. Empty string means the active document, and '*' means all document"
      "\nresolve - whether to resolve the subname references."
      "\n          0: do not resolve, 1: resolve, 2: resolve with element map"
      "\nindex - select stack index, 0 is the last pushed selection, positive index to trace further back,\n"