fixed InceptionV3 dygraph class creation is not wrapped with fluid.dygraph.guard()

ppgan/metric/compute_fid.py

@@ -250,9 +250,10 @@ def calculate_fid_given_paths(paths,
         if not os.path.exists(p):
             raise RuntimeError('Invalid path: %s' % p)
 
-    if model is None:
-        block_idx = InceptionV3.BLOCK_INDEX_BY_DIM[dims]
-        model = InceptionV3([block_idx], class_dim=1008)
+    if model is None and style != 'stargan':
+        with fluid.dygraph.guard():
+            block_idx = InceptionV3.BLOCK_INDEX_BY_DIM[dims]
+            model = InceptionV3([block_idx], class_dim=1008)
 
     m1, s1 = _compute_statistics_of_path(paths[0], model, batch_size, dims,
                                          use_gpu, premodel_path, style)