GH-38341: [Python] Remove usage of pandas internals DatetimeTZBlock (#38321)

jorisvandenbossche · web-flow · commit 6b93c4a0e8cb · 2024-01-08T14:21:10.000+01:00
### Rationale for this change This usage probably stems from a long time ago that it was required to specify the Block type, but nowadays it's good enough to just specify the dtype, and thus cutting down on our usage of internal pandas objects. Part of #35081 * Closes: #38341 Authored-by: Joris Van den Bossche <jorisvandenbossche@gmail.com> Signed-off-by: Joris Van den Bossche <jorisvandenbossche@gmail.com>
diff --git a/python/pyarrow/pandas_compat.py b/python/pyarrow/pandas_compat.py
@@ -717,9 +717,15 @@ def _reconstruct_block(item, columns=None, extension_columns=None):
     elif 'timezone' in item:
         unit, _ = np.datetime_data(block_arr.dtype)
         dtype = make_datetimetz(unit, item['timezone'])
-        block = _int.make_block(block_arr, placement=placement,
-                                klass=_int.DatetimeTZBlock,
-                                dtype=dtype)
+        if _pandas_api.is_ge_v21():
+            pd_arr = _pandas_api.pd.array(
+                block_arr.view("int64"), dtype=dtype, copy=False
+            )
+            block = _int.make_block(pd_arr, placement=placement)
+        else:
+            block = _int.make_block(block_arr, placement=placement,
+                                    klass=_int.DatetimeTZBlock,
+                                    dtype=dtype)
     elif 'py_array' in item:
         # create ExtensionBlock
         arr = item['py_array']
