attempt to fix compilation issue (menustrings.py)

        (merge https://trac.osgeo.org/grass/changeset/53555 from relbr64)


git-svn-id: https://svn.osgeo.org/grass/grass/trunk@53557 15284696-431f-4ddb-bdfa-cd5b030d7da7

gui/wxpython/core/debug.py

@@ -11,7 +11,7 @@ from core.debug import Debug
 Debug.msg (3, 'debug message')
 @endcode
          
-(C) 2007-2009, 2011 by the GRASS Development Team
+(C) 2007-2009, 2011-2012 by the GRASS Development Team
 
 This program is free software under the GNU General Public License
 (>=v2). Read the file COPYING that comes with GRASS for details.
@@ -22,8 +22,6 @@ This program is free software under the GNU General Public License
 import os
 import sys
 
-import grass.script as grass
-
 class DebugMsg:
     """!wxGUI debugging
     
@@ -32,14 +30,17 @@ class DebugMsg:
     @endcode
     """
     def __init__(self):
-        # default level
-        self.debuglevel = 0
-        
-        self.SetLevel()
+        self.SetLevel() # -> default debug level
 
     def SetLevel(self):
         """!Initialize gui debug level
         """
+        try:
+            import grass.script as grass
+        except ImportError:
+            self.debuglevel = 0
+            return
+        
         self.debuglevel = int(grass.gisenv().get('WX_DEBUG', 0))
         
     def msg(self, level, message, *args):