diff --git a/pygtk.py b/pygtk.py
index e061b88..69664d9 100644
--- a/pygtk.py
+++ b/pygtk.py
@@ -37,27 +37,26 @@ _pygtk_required_version = None
 def _get_available_versions():
     versions = {}
     for dir in sys.path:
-        if not dir: 
+        if not dir:
             dir = os.getcwd()
-            
+
         if not os.path.isdir(dir):
             continue
-        
+
         # if the dir is a pygtk dir, skip it
         if fnmatch.fnmatchcase(os.path.basename(dir), _pygtk_dir_pat):
-            continue  
-        
+            continue
+
         for filename in glob.glob(os.path.join(dir, _pygtk_dir_pat)):
             pathname = os.path.join(dir, filename)
 
             # skip non directories
             if not os.path.isdir(pathname):
                 continue
-            
+
             # skip empty directories
             if not os.listdir(pathname):
                 continue
-            
             if not versions.has_key(filename[-3:]):
                 versions[filename[-3:]] = pathname
     return versions
@@ -69,7 +68,7 @@ def require20():
 def require(version):
     if version == '2.0':
         return require20()
-    
+
     global _pygtk_required_version
 
     if _pygtk_required_version != None:
@@ -91,5 +90,5 @@ def require(version):
 
     # prepend the pygtk path ...
     sys.path.insert(0, versions[version])
-    
+
     _pygtk_required_version = version
