MNT: Prevent errors at GC (Image), and when files are removed before

atexit (settings)

fsl/data/image.py

@@ -1206,7 +1206,8 @@ class Image(Nifti):
 
     def __del__(self):
         """Closes any open file handles, and clears some references. """
-        Nifti.__del__(self)
+        if Nifti is not None:
+            Nifti.__del__(self)
         self.__nibImage     = None
         self.__imageWrapper = None
 

fsl/utils/settings.py

@@ -421,7 +421,7 @@ class Settings(object):
         try:
             with open(configFile, 'wb') as f:
                 pickle.dump(config, f, protocol=2)
-        except (IOError, pickle.PicklingError, EOFError):
+        except (IOError, pickle.PicklingError, EOFError, FileNotFoundError):
             log.warning('Unable to save {} configuration file '
                         '{}'.format(self.__configID, configFile),
                         exc_info=True)