diff --git a/src/diffpy/__init__.py b/src/diffpy/__init__.py
index 2efe939..04d8ace 100644
--- a/src/diffpy/__init__.py
+++ b/src/diffpy/__init__.py
@@ -14,13 +14,3 @@
 # See LICENSE.rst for license information.
 #
 ##############################################################################
-"""diffpy - tools for structure analysis by diffraction.
-
-Blank namespace package for module diffpy."""
-
-
-from pkgutil import extend_path
-
-__path__ = extend_path(__path__, __name__)
-
-# End of file
diff --git a/src/diffpy/pdffit2/version.py b/src/diffpy/pdffit2/version.py
index 8615928..7a1eaaa 100644
--- a/src/diffpy/pdffit2/version.py
+++ b/src/diffpy/pdffit2/version.py
@@ -7,17 +7,22 @@
 # File coded by: Billinge Group members and community contributors.
 #
 # See GitHub contributions for a more detailed list of contributors.
-# https://github.com/diffpy/diffpy.pdffit2/graphs/contributors
+# https://github.com/diffpy/diffpy.pdffit2/graphs/contributors  # noqa: E501
 #
 # See LICENSE.rst for license information.
 #
 ##############################################################################
 """Definition of __version__."""
 
+#  We do not use the other three variables, but can be added back if needed.
+#  __all__ = ["__date__", "__git_commit__", "__timestamp__", "__version__"]
+
 import datetime
 import json
 import urllib.request
-from importlib.metadata import version
+
+# obtain version information
+from importlib.metadata import PackageNotFoundError, version
 from pathlib import Path
 
 
@@ -57,9 +62,9 @@ def get_pypi_release_date(package_name, timeout=5):
     return str(release_date)
 
 
-__version__ = version("diffpy.pdffit2")
 __date__ = get_pypi_release_date("diffpy.pdffit2")
 
-# End of file
-
-# Release date: 2025-02-07
+try:
+    __version__ = version("diffpy.pdffit2")
+except PackageNotFoundError:
+    __version__ = "unknown"
diff --git a/tests/test_exceptions.py b/tests/test_exceptions.py
index 83f2b37..07a4f4e 100644
--- a/tests/test_exceptions.py
+++ b/tests/test_exceptions.py
@@ -18,7 +18,8 @@
 
 import pytest
 
-from diffpy.pdffit2 import PdfFit, pdffit2
+from diffpy.pdffit2 import pdffit2
+from diffpy.pdffit2.pdffit import PdfFit
 
 
 class read_structExceptions(unittest.TestCase):
diff --git a/tests/test_pdffit.py b/tests/test_pdffit.py
index 7336f0e..54b1a1c 100644
--- a/tests/test_pdffit.py
+++ b/tests/test_pdffit.py
@@ -6,7 +6,8 @@
 
 import pytest
 
-from diffpy.pdffit2 import PdfFit, pdffit2
+from diffpy.pdffit2 import pdffit2
+from diffpy.pdffit2.pdffit import PdfFit
 from diffpy.structure import loadStructure
 
 # ----------------------------------------------------------------------------
diff --git a/tests/test_phase_fractions.py b/tests/test_phase_fractions.py
index ac33ec6..c86961e 100644
--- a/tests/test_phase_fractions.py
+++ b/tests/test_phase_fractions.py
@@ -6,7 +6,7 @@
 
 import pytest
 
-from diffpy.pdffit2 import PdfFit
+from diffpy.pdffit2.pdffit import PdfFit
 
 
 ##############################################################################
diff --git a/tests/test_shape_factors.py b/tests/test_shape_factors.py
index 110ce55..70424e5 100644
--- a/tests/test_shape_factors.py
+++ b/tests/test_shape_factors.py
@@ -8,7 +8,8 @@
 import numpy
 import pytest
 
-from diffpy.pdffit2 import PdfFit, pdffit2
+from diffpy.pdffit2 import pdffit2
+from diffpy.pdffit2.pdffit import PdfFit
 
 
 def spherefactor(r, d):