[fix] config ignore imported modules and functions (#1802)

* [fix] config ignore modules and functions

* add unitest

mmcv/utils/config.py

@@ -7,6 +7,7 @@ import platform
 import shutil
 import sys
 import tempfile
+import types
 import uuid
 import warnings
 from argparse import Action, ArgumentParser
@@ -209,6 +210,8 @@ class Config:
                     name: value
                     for name, value in mod.__dict__.items()
                     if not name.startswith('__')
+                    and not isinstance(value, types.ModuleType)
+                    and not isinstance(value, types.FunctionType)
                 }
                 # delete imported module
                 del sys.modules[temp_module_name]

tests/data/config/l.py

 # Copyright (c) OpenMMLab. All rights reserved.
+import os.path as osp
+
+
+def func(x):
+    return x
+
 _base_ = ['./l1.py', './l2.yaml', './l3.json', './l4.py']
 item3 = False
 item4 = 'test'

tests/data/config/n.py

 # Copyright (c) OpenMMLab. All rights reserved.
+import os.path as osp
+
+
+def func(x):
+    return x
+
 test_item1 = [1, 2]
 bool_item2 = True
 str_item3 = 'test'