diff --git a/dso/dso/utils.py b/dso/dso/utils.py
index e33bcb7..bbbb012 100644
--- a/dso/dso/utils.py
+++ b/dso/dso/utils.py
@@ -1,6 +1,5 @@
 """Utility functions used in deep symbolic optimization."""
 
-import collections
 import copy
 import functools
 import numpy as np
@@ -10,6 +9,11 @@
 import os
 import pandas as pd
 
+try:
+    from collections.abc import Mapping
+except ImportError:
+    from collections import Mapping
+
 
 def is_float(s):
     """Determine whether the input variable can be cast to float."""
@@ -154,7 +158,7 @@ def safe_merge_dicts(base_dict, update_dict):
         return update_dict
     base_dict = copy.deepcopy(base_dict)
     for key, value in update_dict.items():
-        if isinstance(value, collections.Mapping):
+        if isinstance(value, Mapping):
             base_dict[key] = safe_merge_dicts(base_dict.get(key, {}), value)
         else:
             base_dict[key] = value