diff --git a/pyevolve/G1DBinaryString.py b/pyevolve/G1DBinaryString.py
index f07d19e..a1fb683 100644
--- a/pyevolve/G1DBinaryString.py
+++ b/pyevolve/G1DBinaryString.py
@@ -53,7 +53,7 @@ class G1DBinaryString(G1DBase):
    :param length: the 1D Binary String size
 
    """
-   __slots__ = [ "stringLength" ]
+   __slots__ = ["stringLength"]
 
    def __init__(self, length=10):
       """ The initializator of G1DList representation """
diff --git a/pyevolve/G2DBinaryString.py b/pyevolve/G2DBinaryString.py
index e6a78d5..2b2bdab 100644
--- a/pyevolve/G2DBinaryString.py
+++ b/pyevolve/G2DBinaryString.py
@@ -58,12 +58,12 @@ class G2DBinaryString(GenomeBase):
     :param width: the number of columns
 
     """
-    __slots__ = [ "height", "width", "genomeString" ]
+    __slots__ = ["height", "width", "genomeString"]
 
     def __init__(self, height, width):
         """ The initializator of G2DBinaryString representation,
         height and width must be specified """
-        super(G2DBinaryString ,self).__init__()
+        super(G2DBinaryString, self).__init__()
         self.height = height
         self.width = width
 
diff --git a/pyevolve/G2DList.py b/pyevolve/G2DList.py
index 940b7f2..6c864e3 100644
--- a/pyevolve/G2DList.py
+++ b/pyevolve/G2DList.py
@@ -87,7 +87,7 @@ class G2DList(GenomeBase):
 
     """
 
-    __slots__ = [ "height", "width", "genomeList" ]
+    __slots__ = ["height", "width", "genomeList"]
 
     def __init__(self, height, width, cloning=False):
         """ The initializator of G2DList representation,
diff --git a/pyevolve/GTree.py b/pyevolve/GTree.py
index ac6d6b8..381580d 100644
--- a/pyevolve/GTree.py
+++ b/pyevolve/GTree.py
@@ -101,7 +101,7 @@ class GTreeNode(GTreeNodeBase):
     :param parent: the parent node, if root, this
                    must be *None*
     """
-    __slots__ = [ "node_data" ]
+    __slots__ = ["node_data"]
 
     def __init__(self, data, parent=None):
         super(GTreeNode, self).__init__(parent)
@@ -239,7 +239,7 @@ class GTreeNodeGP(GTreeNodeBase):
     :param parent: the node parent
 
     """
-    __slots__ = [ "node_type", "node_data" ]
+    __slots__ = ["node_type", "node_data"]
 
     def __init__(self, data, node_type=0, parent=None):
         super(GTreeNodeGP, self).__init__(parent)
diff --git a/pyevolve/GenomeBase.py b/pyevolve/GenomeBase.py
index 5642a31..f22b1cf 100644
--- a/pyevolve/GenomeBase.py
+++ b/pyevolve/GenomeBase.py
@@ -16,7 +16,7 @@
 
 class GenomeBase(object):
    """ GenomeBase Class - The base of all chromosome representation """
-   __slots__ = [ "evaluator", "initializator", "mutator", "crossover", "internalParams", "score", "fitness" ]
+   __slots__ = ["evaluator", "initializator", "mutator", "crossover", "internalParams", "score", "fitness"]
 
    def __init__(self):
       """Genome Constructor"""
@@ -47,8 +47,8 @@ def getFitnessScore(self):
 
    def __repr__(self):
       """String representation of Genome"""
-      allSlots = [ self.evaluator, self.initializator,
-                   self.mutator, self.crossover ]
+      allSlots = [self.evaluator, self.initializator, self.mutator,
+                  self.crossover]
 
       ret = "- GenomeBase\n"
       ret += "\tScore:\t\t\t %.6f\n" % (self.score,)
@@ -166,7 +166,7 @@ class G1DBase(GenomeBase):
    .. versionadded:: 0.6
       Added the *G1DBase* class
    """
-   __slots__ = [ "genomeSize", "genomeList" ]
+   __slots__ = ["genomeSize", "genomeList"]
 
    def __init__(self, size):
       super(G1DBase, self).__init__()
@@ -285,7 +285,7 @@ class GTreeNodeBase(object):
    .. versionadded:: 0.6
       Added the *GTreeNodeBase* class
    """
-   __slots__ = [ "parent", "childs" ]
+   __slots__ = ["parent", "childs"]
 
    def __init__(self, parent, childs=None):
       self.parent = parent
@@ -399,7 +399,7 @@ class GTreeBase(GenomeBase):
    .. versionadded:: 0.6
       Added the *GTreeBase* class
    """
-   __slots__ = [ "root_node", "tree_height", "nodes_list", "nodes_leaf", "nodes_branch" ]
+   __slots__ = ["root_node", "tree_height", "nodes_list", "nodes_leaf", "nodes_branch"]
 
    def __init__(self, root_node):
       super(GTreeBase, self).__init__()