this should fix #75: continuing problems with numpy0.12.18

1 files changed, 2 insertions, 1 deletions

diff --git a/resolver.py b/resolver.py
index 366d8ff..b0e8105 100644
--- a/resolver.py
+++ b/resolver.py
@@ -3,6 +3,7 @@
 from __future__ import absolute_import
 
 import re
+import copy
 
 from typing import Any, Dict  # NOQA
 
@@ -38,7 +39,7 @@ class BaseResolver(object):
     def add_implicit_resolver(cls, tag, regexp, first):
         # type: (Any, Any, Any) -> None
         if 'yaml_implicit_resolvers' not in cls.__dict__:
-            cls.yaml_implicit_resolvers = cls.yaml_implicit_resolvers.copy()
+            cls.yaml_implicit_resolvers = copy.deepcopy(cls.yaml_implicit_resolvers)
         if first is None:
             first = [None]
         for ch in first: