Revert "Make a Dwh class singleton instead of creating a child class"

This reverts commit 7bef033.

src/pyprediktorutilities/dwh.py

@@ -10,7 +10,7 @@
 logger.addHandler(logging.NullHandler())
 
 
-class Dwh(metaclass=singleton_class.SingletonMeta):
+class Dwh:
     """Access a PowerView Data Warehouse or other SQL databases.
 
     Args:
@@ -304,3 +304,11 @@ def __disconnect(self) -> None:
     def __commit(self) -> None:
         """Commits any changes to the database."""
         self.connection.commit()
+
+
+class DwhSingleton(Dwh, metaclass=singleton_class.SingletonMeta):
+    pass
+
+
+def get_dwh_instance(*args, **kwargs):
+    return DwhSingleton(*args, **kwargs)

tests/test_dwh.py

@@ -6,7 +6,7 @@
 import pandas as pd
 
 from unittest.mock import Mock
-from pyprediktorutilities.dwh import Dwh
+from pyprediktorutilities.dwh import Dwh, get_dwh_instance
 from pandas.testing import assert_frame_equal
 
 """
@@ -797,10 +797,10 @@ def test_dwh_singleton_can_be_created_only_once(monkeypatch):
         "pyprediktorutilities.dwh.pyodbc.connect", mock_pyodbc_connection
     )
 
-    db = Dwh(grs(), grs(), grs(), grs(), driver_index)
+    db = get_dwh_instance(grs(), grs(), grs(), grs(), driver_index)
     db_instance_address = id(db)
 
-    db_2 = Dwh(grs(), grs(), grs(), grs(), driver_index)
+    db_2 = get_dwh_instance(grs(), grs(), grs(), grs(), driver_index)
     db_2_instance_address = id(db_2)
 
     assert db_instance_address == db_2_instance_address