diff --git a/pyRMT.py b/pyRMT.py
index c023a4c..d46371c 100644
--- a/pyRMT.py
+++ b/pyRMT.py
@@ -61,7 +61,7 @@
 from __future__ import division, print_function
 from builtins import reversed
 from builtins import map, zip
-from collections import MutableSequence, Sequence
+from collections.abc import MutableSequence, Sequence
 import copy
 from math import ceil
 from numbers import Complex, Integral, Real