--- a/src/tools/xml_tools.py	Tue Aug 18 10:36:41 2015 +0200
+++ b/src/tools/xml_tools.py	Tue Aug 18 10:52:18 2015 +0200
@@ -338,7 +338,7 @@
         @param xmlui: XMLUI instance
         @parent: parent element
         """
-        assert(self.type) is not None
+        assert self.type is not None
         if not hasattr(self, 'elem'):
             self.elem = parent.xmlui.doc.createElement(self.type)
         self.xmlui = xmlui
@@ -377,7 +377,7 @@
     type = 'field_back'
 
     def __init__(self, parent, name):
-        assert(isinstance(parent, ButtonWidget))
+        assert isinstance(parent, ButtonWidget)
         super(FieldBackElement, self).__init__(parent.xmlui, parent)
         self.elem.setAttribute('name', name)
 
@@ -397,7 +397,7 @@
 
     def __init__(self, parent, children):
         super(InternalDataElement, self).__init__(parent.xmlui, parent)
-        assert(isinstance(children, list))
+        assert isinstance(children, list)
         for child in children:
             self.elem.childNodes.append(child)
 
@@ -413,7 +413,7 @@
         @param option (string, tuple)
         @param selected (boolean)
         """
-        assert(isinstance(parent, ListWidget))
+        assert isinstance(parent, ListWidget)
         super(OptionElement, self).__init__(parent.xmlui, parent)
         if isinstance(option, basestring):
             value, label = option, option
@@ -432,7 +432,7 @@
     type = 'row'
 
     def __init__(self, parent):
-        assert(isinstance(parent, AdvancedListContainer))
+        assert isinstance(parent, AdvancedListContainer)
         super(RowElement, self).__init__(parent.xmlui, parent)
         if parent.next_row_idx is not None:
             if parent.auto_index:
@@ -452,7 +452,7 @@
         @param label: label to be displayed in columns
         @param description: long descriptive text
         """
-        assert(isinstance(parent, AdvancedListContainer))
+        assert isinstance(parent, AdvancedListContainer)
         super(HeaderElement, self).__init__(parent.xmlui, parent)
         if name:
             self.elem.setAttribute('name', name)
@@ -830,7 +830,7 @@
         else:
             selected = []
         for option in options:
-            assert(isinstance(option, basestring) or isinstance(option, tuple))
+            assert isinstance(option, basestring) or isinstance(option, tuple)
             value = option if isinstance(option, basestring) else option[0]
             OptionElement(self, option, value in selected)
 
@@ -1073,7 +1073,7 @@
             self.current_container = self._createContainer(container, self.current_container.getParentContainer() or self.main_container, **kwargs)
         else:
             self.current_container = self.main_container if container is None else container
-        assert(isinstance(self.current_container, Container))
+        assert isinstance(self.current_container, Container)
         return self.current_container
 
     def addWidget(self, type_, *args, **kwargs):