From b079f75feb97d65c97f8f171d63a2c7bf5b7c568 Mon Sep 17 00:00:00 2001
From: jbrockmendel <jbrockmendel@gmail.com>
Date: Tue, 10 Dec 2019 15:13:17 -0800
Subject: [PATCH 1/3] CLN: remove redundant Index checks

---
 pandas/core/indexes/base.py | 13 -------------
 1 file changed, 13 deletions(-)

diff --git a/pandas/core/indexes/base.py b/pandas/core/indexes/base.py
index 1587d97ffb52c..60637e08dedfb 100644
--- a/pandas/core/indexes/base.py
+++ b/pandas/core/indexes/base.py
@@ -732,24 +732,11 @@ def astype(self, dtype, copy=True):
             from .category import CategoricalIndex
 
             return CategoricalIndex(self.values, name=self.name, dtype=dtype, copy=copy)
-        elif is_datetime64tz_dtype(dtype):
-            # TODO(GH-24559): Remove this block, use the following elif.
-            # avoid FutureWarning from DatetimeIndex constructor.
-            from pandas import DatetimeIndex
-
-            tz = pandas_dtype(dtype).tz
-            return DatetimeIndex(np.asarray(self)).tz_localize("UTC").tz_convert(tz)
 
         elif is_extension_array_dtype(dtype):
             return Index(np.asarray(self), dtype=dtype, copy=copy)
 
         try:
-            if is_datetime64tz_dtype(dtype):
-                from pandas import DatetimeIndex
-
-                return DatetimeIndex(
-                    self.values, name=self.name, dtype=dtype, copy=copy
-                )
             return Index(
                 self.values.astype(dtype, copy=copy), name=self.name, dtype=dtype
             )

From de8f811067bb5bd6b882d40310994972a1696804 Mon Sep 17 00:00:00 2001
From: jbrockmendel <jbrockmendel@gmail.com>
Date: Tue, 10 Dec 2019 17:45:44 -0800
Subject: [PATCH 2/3] fixup unused import

---
 pandas/core/index.py          | 7 +++++++
 pandas/core/indexes/base.py   | 1 -
 pandas/core/indexes/period.py | 1 +
 3 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/pandas/core/index.py b/pandas/core/index.py
index 84b37b8bd659d..c7c6f52f18a11 100644
--- a/pandas/core/index.py
+++ b/pandas/core/index.py
@@ -19,3 +19,10 @@
     get_objs_combined_axis,
 )
 from pandas.core.indexes.multi import _sparsify  # noqa:F401
+
+import warnings
+warnings.warn(
+    "pandas.core.index is deprecated and will be removed in a future version.  "
+    "Use pandas.core.indexes.api instead.",
+    FutureWarning,
+)
diff --git a/pandas/core/indexes/base.py b/pandas/core/indexes/base.py
index 60637e08dedfb..803c29c327b8e 100644
--- a/pandas/core/indexes/base.py
+++ b/pandas/core/indexes/base.py
@@ -45,7 +45,6 @@
     is_signed_integer_dtype,
     is_timedelta64_dtype,
     is_unsigned_integer_dtype,
-    pandas_dtype,
 )
 from pandas.core.dtypes.concat import concat_compat
 from pandas.core.dtypes.generic import (
diff --git a/pandas/core/indexes/period.py b/pandas/core/indexes/period.py
index d63de10d92921..003b9dd8d0eb4 100644
--- a/pandas/core/indexes/period.py
+++ b/pandas/core/indexes/period.py
@@ -261,6 +261,7 @@ def _simple_new(cls, values, name=None, freq=None, **kwargs):
         # TODO: raising on floats is tested, but maybe not useful.
         # Should the callers know not to pass floats?
         # At the very least, I think we can ensure that lists aren't passed.
+        assert not isinstance(values, list)
         if isinstance(values, list):
             values = np.asarray(values)
         if is_float_dtype(values):

From 21d0d6a47a9ebc80fb99cf8d122d0d09917e6632 Mon Sep 17 00:00:00 2001
From: jbrockmendel <jbrockmendel@gmail.com>
Date: Tue, 10 Dec 2019 19:22:12 -0800
Subject: [PATCH 3/3] revert unwanted changes

---
 pandas/core/index.py          | 7 -------
 pandas/core/indexes/period.py | 1 -
 2 files changed, 8 deletions(-)

diff --git a/pandas/core/index.py b/pandas/core/index.py
index c7c6f52f18a11..84b37b8bd659d 100644
--- a/pandas/core/index.py
+++ b/pandas/core/index.py
@@ -19,10 +19,3 @@
     get_objs_combined_axis,
 )
 from pandas.core.indexes.multi import _sparsify  # noqa:F401
-
-import warnings
-warnings.warn(
-    "pandas.core.index is deprecated and will be removed in a future version.  "
-    "Use pandas.core.indexes.api instead.",
-    FutureWarning,
-)
diff --git a/pandas/core/indexes/period.py b/pandas/core/indexes/period.py
index 003b9dd8d0eb4..d63de10d92921 100644
--- a/pandas/core/indexes/period.py
+++ b/pandas/core/indexes/period.py
@@ -261,7 +261,6 @@ def _simple_new(cls, values, name=None, freq=None, **kwargs):
         # TODO: raising on floats is tested, but maybe not useful.
         # Should the callers know not to pass floats?
         # At the very least, I think we can ensure that lists aren't passed.
-        assert not isinstance(values, list)
         if isinstance(values, list):
             values = np.asarray(values)
         if is_float_dtype(values):