diff --git a/.github/workflows/pytest.yml b/.github/workflows/pytest.yml
index 6081f94..880a3a3 100644
--- a/.github/workflows/pytest.yml
+++ b/.github/workflows/pytest.yml
@@ -5,7 +5,7 @@ name: Python package
 
 on:
   push:
-    branches: [ master ]
+    branches: [ master, issue60 ]
   pull_request:
     branches: [ master ]
 
@@ -30,6 +30,7 @@ jobs:
         python -m pip install flake8 pytest
         python -m pip install -e .
         if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
+        python -m pip list
     - name: Lint with flake8
       run: |
         # stop the build if there are Python syntax errors or undefined names
diff --git a/pyfive/dataobjects.py b/pyfive/dataobjects.py
index dcdef0a..5d4b79e 100644
--- a/pyfive/dataobjects.py
+++ b/pyfive/dataobjects.py
@@ -187,7 +187,7 @@ def unpack_attribute(self, offset):
 
         # read in the dataspace information
         shape, maxshape = determine_data_shape(self.msg_data, offset)
-        items = int(np.product(shape))
+        items = int(np.prod(shape))
         offset += _padded_size(attr_dict['dataspace_size'], padding_multiple)
 
         # read in the value(s)