From 542032cbaf863ec87358265d368bfe9e541d4098 Mon Sep 17 00:00:00 2001
From: shubham11941140 <63910248+shubham11941140@users.noreply.github.com>
Date: Fri, 5 Nov 2021 09:54:11 +0530
Subject: [PATCH 01/19] import error resolved

---
 pandas/core/dtypes/common.py   | 2 +-
 pandas/tests/base/test_misc.py | 4 ++++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/pandas/core/dtypes/common.py b/pandas/core/dtypes/common.py
index 815a0a2040ddb..742a1e025ef8c 100644
--- a/pandas/core/dtypes/common.py
+++ b/pandas/core/dtypes/common.py
@@ -601,7 +601,7 @@ def is_dtype_equal(source, target) -> bool:
             #  is_dtype_equal(CDT, "category") and CDT == "category"
             try:
                 src = get_dtype(source)
-                if isinstance(src, ExtensionDtype):
+                if isinstance(src, ExtensionDtype) or isinstance(src, np.dtype):
                     return src == target
             except (TypeError, AttributeError):
                 return False
diff --git a/pandas/tests/base/test_misc.py b/pandas/tests/base/test_misc.py
index c0250e2b3e958..efb2a8bdfe7f6 100644
--- a/pandas/tests/base/test_misc.py
+++ b/pandas/tests/base/test_misc.py
@@ -11,6 +11,7 @@
 from pandas.core.dtypes.common import (
     is_categorical_dtype,
     is_object_dtype,
+    is_dtype_equal
 )
 
 import pandas as pd
@@ -150,6 +151,9 @@ def test_access_by_position(index):
     assert index[-1] == index[size - 1]
 
     msg = f"index {size} is out of bounds for axis 0 with size {size}"
+
+    assert not is_dtype_equal(index.dtype, "string[pyarrow]")
+
     with pytest.raises(IndexError, match=msg):
         index[size]
     msg = "single positional indexer is out-of-bounds"

From 76ab6fa0d822e7ca4ad3cd0b5f4cf797ac354597 Mon Sep 17 00:00:00 2001
From: shubham11941140 <63910248+shubham11941140@users.noreply.github.com>
Date: Sat, 6 Nov 2021 00:20:03 +0530
Subject: [PATCH 02/19] pre-commit

---
 pandas/core/dtypes/common.py   | 1 +
 pandas/tests/base/test_misc.py | 1 -
 2 files changed, 1 insertion(+), 1 deletion(-)

diff --git a/pandas/core/dtypes/common.py b/pandas/core/dtypes/common.py
index 742a1e025ef8c..4a45437a7491f 100644
--- a/pandas/core/dtypes/common.py
+++ b/pandas/core/dtypes/common.py
@@ -602,6 +602,7 @@ def is_dtype_equal(source, target) -> bool:
             try:
                 src = get_dtype(source)
                 if isinstance(src, ExtensionDtype) or isinstance(src, np.dtype):
+
                     return src == target
             except (TypeError, AttributeError):
                 return False
diff --git a/pandas/tests/base/test_misc.py b/pandas/tests/base/test_misc.py
index efb2a8bdfe7f6..a3cfe6e813711 100644
--- a/pandas/tests/base/test_misc.py
+++ b/pandas/tests/base/test_misc.py
@@ -153,7 +153,6 @@ def test_access_by_position(index):
     msg = f"index {size} is out of bounds for axis 0 with size {size}"
 
     assert not is_dtype_equal(index.dtype, "string[pyarrow]")
-
     with pytest.raises(IndexError, match=msg):
         index[size]
     msg = "single positional indexer is out-of-bounds"

From c82d836b8f76b45ed82c7c082ace68da513b0781 Mon Sep 17 00:00:00 2001
From: shubham11941140 <63910248+shubham11941140@users.noreply.github.com>
Date: Sat, 6 Nov 2021 00:22:16 +0530
Subject: [PATCH 03/19] Update test_misc.py

---
 pandas/tests/base/test_misc.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pandas/tests/base/test_misc.py b/pandas/tests/base/test_misc.py
index a3cfe6e813711..1216dee6acb50 100644
--- a/pandas/tests/base/test_misc.py
+++ b/pandas/tests/base/test_misc.py
@@ -10,8 +10,8 @@
 
 from pandas.core.dtypes.common import (
     is_categorical_dtype,
+    is_dtype_equal,
     is_object_dtype,
-    is_dtype_equal
 )
 
 import pandas as pd

From c35e162f14593c1586ec778b7a6a5d991e74d7e2 Mon Sep 17 00:00:00 2001
From: shubham11941140 <63910248+shubham11941140@users.noreply.github.com>
Date: Sun, 7 Nov 2021 11:10:17 +0530
Subject: [PATCH 04/19] Changes done

---
 doc/source/whatsnew/v1.3.5.rst     | 2 +-
 pandas/core/dtypes/common.py       | 2 ++
 pandas/tests/dtypes/test_dtypes.py | 4 ++++
 3 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/doc/source/whatsnew/v1.3.5.rst b/doc/source/whatsnew/v1.3.5.rst
index 589092c0dd7e3..cdc999c4bf230 100644
--- a/doc/source/whatsnew/v1.3.5.rst
+++ b/doc/source/whatsnew/v1.3.5.rst
@@ -24,7 +24,7 @@ Fixed regressions
 
 Bug fixes
 ~~~~~~~~~
--
+- Fixed bug in :bug:`is_dtype_equal` raises if pyarrow not installed (:issue:`44327`)
 -
 
 .. ---------------------------------------------------------------------------
diff --git a/pandas/core/dtypes/common.py b/pandas/core/dtypes/common.py
index 4a45437a7491f..fb8809d423830 100644
--- a/pandas/core/dtypes/common.py
+++ b/pandas/core/dtypes/common.py
@@ -599,6 +599,8 @@ def is_dtype_equal(source, target) -> bool:
         if not isinstance(source, str):
             # GH#38516 ensure we get the same behavior from
             #  is_dtype_equal(CDT, "category") and CDT == "category"
+            # GH-44276 ensures behaviour is consistent
+            # is_dtype_equal (dtype, "string[pyarrow]")
             try:
                 src = get_dtype(source)
                 if isinstance(src, ExtensionDtype) or isinstance(src, np.dtype):
diff --git a/pandas/tests/dtypes/test_dtypes.py b/pandas/tests/dtypes/test_dtypes.py
index 30447de874aaa..b3016c82b2eaf 100644
--- a/pandas/tests/dtypes/test_dtypes.py
+++ b/pandas/tests/dtypes/test_dtypes.py
@@ -115,6 +115,10 @@ def test_construction_from_string(self, dtype):
         with pytest.raises(TypeError, match=msg):
             CategoricalDtype.construct_from_string("foo")
 
+    def test_pyarrow_string_import_error(self, dtype):
+        # GH-44276
+        assert not is_dtype_equal(dtype, "string[pyarrow]")
+
     def test_constructor_invalid(self):
         msg = "Parameter 'categories' must be list-like"
         with pytest.raises(TypeError, match=msg):

From cff657ad17d7f965c2333bc5c259f688f56801d3 Mon Sep 17 00:00:00 2001
From: shubham11941140 <63910248+shubham11941140@users.noreply.github.com>
Date: Sun, 7 Nov 2021 11:19:17 +0530
Subject: [PATCH 05/19] Duplicate test removed

---
 pandas/tests/base/test_misc.py | 2 --
 1 file changed, 2 deletions(-)

diff --git a/pandas/tests/base/test_misc.py b/pandas/tests/base/test_misc.py
index 1216dee6acb50..134c329f26159 100644
--- a/pandas/tests/base/test_misc.py
+++ b/pandas/tests/base/test_misc.py
@@ -10,7 +10,6 @@
 
 from pandas.core.dtypes.common import (
     is_categorical_dtype,
-    is_dtype_equal,
     is_object_dtype,
 )
 
@@ -152,7 +151,6 @@ def test_access_by_position(index):
 
     msg = f"index {size} is out of bounds for axis 0 with size {size}"
 
-    assert not is_dtype_equal(index.dtype, "string[pyarrow]")
     with pytest.raises(IndexError, match=msg):
         index[size]
     msg = "single positional indexer is out-of-bounds"

From dce9db6e109d87b459f7edddd6d08c26512cc335 Mon Sep 17 00:00:00 2001
From: shubham11941140 <63910248+shubham11941140@users.noreply.github.com>
Date: Mon, 8 Nov 2021 09:08:57 +0530
Subject: [PATCH 06/19] Changes done

---
 pandas/core/dtypes/common.py       | 2 +-
 pandas/tests/base/test_misc.py     | 1 -
 pandas/tests/dtypes/test_dtypes.py | 2 ++
 3 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/pandas/core/dtypes/common.py b/pandas/core/dtypes/common.py
index fb8809d423830..6b5c0d7ce66de 100644
--- a/pandas/core/dtypes/common.py
+++ b/pandas/core/dtypes/common.py
@@ -603,7 +603,7 @@ def is_dtype_equal(source, target) -> bool:
             # is_dtype_equal (dtype, "string[pyarrow]")
             try:
                 src = get_dtype(source)
-                if isinstance(src, ExtensionDtype) or isinstance(src, np.dtype):
+                if isinstance(src, (ExtensionDtype, np.dtype)):
 
                     return src == target
             except (TypeError, AttributeError):
diff --git a/pandas/tests/base/test_misc.py b/pandas/tests/base/test_misc.py
index 134c329f26159..c0250e2b3e958 100644
--- a/pandas/tests/base/test_misc.py
+++ b/pandas/tests/base/test_misc.py
@@ -150,7 +150,6 @@ def test_access_by_position(index):
     assert index[-1] == index[size - 1]
 
     msg = f"index {size} is out of bounds for axis 0 with size {size}"
-
     with pytest.raises(IndexError, match=msg):
         index[size]
     msg = "single positional indexer is out-of-bounds"
diff --git a/pandas/tests/dtypes/test_dtypes.py b/pandas/tests/dtypes/test_dtypes.py
index b3016c82b2eaf..5056d768a7b33 100644
--- a/pandas/tests/dtypes/test_dtypes.py
+++ b/pandas/tests/dtypes/test_dtypes.py
@@ -118,6 +118,8 @@ def test_construction_from_string(self, dtype):
     def test_pyarrow_string_import_error(self, dtype):
         # GH-44276
         assert not is_dtype_equal(dtype, "string[pyarrow]")
+        with pytest.raises(ImportError, match="pyarrow"):
+            yield
 
     def test_constructor_invalid(self):
         msg = "Parameter 'categories' must be list-like"

From 5abfa2efe4a54775cc3d8ab5a8db8d90a8ca1454 Mon Sep 17 00:00:00 2001
From: shubham11941140 <63910248+shubham11941140@users.noreply.github.com>
Date: Mon, 8 Nov 2021 22:21:29 +0530
Subject: [PATCH 07/19] raises modified

---
 doc/source/whatsnew/v1.3.5.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/doc/source/whatsnew/v1.3.5.rst b/doc/source/whatsnew/v1.3.5.rst
index cdc999c4bf230..4a0f536ac1682 100644
--- a/doc/source/whatsnew/v1.3.5.rst
+++ b/doc/source/whatsnew/v1.3.5.rst
@@ -24,7 +24,7 @@ Fixed regressions
 
 Bug fixes
 ~~~~~~~~~
-- Fixed bug in :bug:`is_dtype_equal` raises if pyarrow not installed (:issue:`44327`)
+- Fixed bug in :bug:`is_dtype_equal` raising if pyarrow not installed (:issue:`44327`)
 -
 
 .. ---------------------------------------------------------------------------

From fb0bd2ad16cab5c0351c049b1b6f40c578695211 Mon Sep 17 00:00:00 2001
From: shubham11941140 <63910248+shubham11941140@users.noreply.github.com>
Date: Tue, 23 Nov 2021 21:52:25 +0530
Subject: [PATCH 08/19] changes done

---
 doc/source/whatsnew/v1.3.5.rst     | 2 +-
 doc/source/whatsnew/v1.4.0.rst     | 2 +-
 pandas/tests/dtypes/test_dtypes.py | 3 +--
 3 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/doc/source/whatsnew/v1.3.5.rst b/doc/source/whatsnew/v1.3.5.rst
index 4a0f536ac1682..589092c0dd7e3 100644
--- a/doc/source/whatsnew/v1.3.5.rst
+++ b/doc/source/whatsnew/v1.3.5.rst
@@ -24,7 +24,7 @@ Fixed regressions
 
 Bug fixes
 ~~~~~~~~~
-- Fixed bug in :bug:`is_dtype_equal` raising if pyarrow not installed (:issue:`44327`)
+-
 -
 
 .. ---------------------------------------------------------------------------
diff --git a/doc/source/whatsnew/v1.4.0.rst b/doc/source/whatsnew/v1.4.0.rst
index 4d0dee01f05c1..7942b53b3ff33 100644
--- a/doc/source/whatsnew/v1.4.0.rst
+++ b/doc/source/whatsnew/v1.4.0.rst
@@ -509,7 +509,7 @@ Conversion
 
 Strings
 ^^^^^^^
--
+- Fixed bug in :bug:`is_dtype_equal` raising if pyarrow not installed (:issue:`44327`)
 -
 
 Interval
diff --git a/pandas/tests/dtypes/test_dtypes.py b/pandas/tests/dtypes/test_dtypes.py
index 5056d768a7b33..f99c49888eaff 100644
--- a/pandas/tests/dtypes/test_dtypes.py
+++ b/pandas/tests/dtypes/test_dtypes.py
@@ -118,8 +118,7 @@ def test_construction_from_string(self, dtype):
     def test_pyarrow_string_import_error(self, dtype):
         # GH-44276
         assert not is_dtype_equal(dtype, "string[pyarrow]")
-        with pytest.raises(ImportError, match="pyarrow"):
-            yield
+        pytest.importorskip("pyarrow")
 
     def test_constructor_invalid(self):
         msg = "Parameter 'categories' must be list-like"

From f7b88885b918bc6479772f79070fa11e55660df2 Mon Sep 17 00:00:00 2001
From: shubham11941140 <63910248+shubham11941140@users.noreply.github.com>
Date: Fri, 26 Nov 2021 00:06:59 +0530
Subject: [PATCH 09/19] decorator fix

---
 pandas/tests/dtypes/test_dtypes.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pandas/tests/dtypes/test_dtypes.py b/pandas/tests/dtypes/test_dtypes.py
index f99c49888eaff..030a309e324f5 100644
--- a/pandas/tests/dtypes/test_dtypes.py
+++ b/pandas/tests/dtypes/test_dtypes.py
@@ -115,10 +115,10 @@ def test_construction_from_string(self, dtype):
         with pytest.raises(TypeError, match=msg):
             CategoricalDtype.construct_from_string("foo")
 
+    @pytest.importorskip("pyarrow")
     def test_pyarrow_string_import_error(self, dtype):
         # GH-44276
         assert not is_dtype_equal(dtype, "string[pyarrow]")
-        pytest.importorskip("pyarrow")
 
     def test_constructor_invalid(self):
         msg = "Parameter 'categories' must be list-like"

From 2de493606e034a41ada00f24644e883ac0b45374 Mon Sep 17 00:00:00 2001
From: shubham11941140 <63910248+shubham11941140@users.noreply.github.com>
Date: Fri, 26 Nov 2021 13:32:51 +0530
Subject: [PATCH 10/19] Changed tests

---
 pandas/tests/dtypes/test_common.py | 5 ++++-
 pandas/tests/dtypes/test_dtypes.py | 5 -----
 2 files changed, 4 insertions(+), 6 deletions(-)

diff --git a/pandas/tests/dtypes/test_common.py b/pandas/tests/dtypes/test_common.py
index 14f6557fbc31e..587310dcee2c0 100644
--- a/pandas/tests/dtypes/test_common.py
+++ b/pandas/tests/dtypes/test_common.py
@@ -127,6 +127,10 @@ def test_dtype_equal(name1, dtype1, name2, dtype2):
     if name1 != name2:
         assert not com.is_dtype_equal(dtype1, dtype2)
 
+@pytest.mark.parametrize("name,dtype", list(dtypes.items()), ids=lambda x: str(x))
+def test_pyarrow_string_import_error(name, dtype):
+    # GH-44276
+    assert not com.is_dtype_equal(dtype, "string[pyarrow]")
 
 @pytest.mark.parametrize(
     "dtype1,dtype2",
@@ -146,7 +150,6 @@ def test_dtype_equal(name1, dtype1, name2, dtype2):
 def test_dtype_equal_strict(dtype1, dtype2):
     assert not com.is_dtype_equal(dtype1, dtype2)
 
-
 def get_is_dtype_funcs():
     """
     Get all functions in pandas.core.dtypes.common that
diff --git a/pandas/tests/dtypes/test_dtypes.py b/pandas/tests/dtypes/test_dtypes.py
index 030a309e324f5..30447de874aaa 100644
--- a/pandas/tests/dtypes/test_dtypes.py
+++ b/pandas/tests/dtypes/test_dtypes.py
@@ -115,11 +115,6 @@ def test_construction_from_string(self, dtype):
         with pytest.raises(TypeError, match=msg):
             CategoricalDtype.construct_from_string("foo")
 
-    @pytest.importorskip("pyarrow")
-    def test_pyarrow_string_import_error(self, dtype):
-        # GH-44276
-        assert not is_dtype_equal(dtype, "string[pyarrow]")
-
     def test_constructor_invalid(self):
         msg = "Parameter 'categories' must be list-like"
         with pytest.raises(TypeError, match=msg):

From 66327e75a71be44c01581f125d2885360a91bfd6 Mon Sep 17 00:00:00 2001
From: shubham11941140 <63910248+shubham11941140@users.noreply.github.com>
Date: Fri, 26 Nov 2021 13:34:57 +0530
Subject: [PATCH 11/19] precommit

---
 pandas/tests/dtypes/test_common.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/pandas/tests/dtypes/test_common.py b/pandas/tests/dtypes/test_common.py
index 587310dcee2c0..4865815e99187 100644
--- a/pandas/tests/dtypes/test_common.py
+++ b/pandas/tests/dtypes/test_common.py
@@ -127,11 +127,13 @@ def test_dtype_equal(name1, dtype1, name2, dtype2):
     if name1 != name2:
         assert not com.is_dtype_equal(dtype1, dtype2)
 
+
 @pytest.mark.parametrize("name,dtype", list(dtypes.items()), ids=lambda x: str(x))
 def test_pyarrow_string_import_error(name, dtype):
     # GH-44276
     assert not com.is_dtype_equal(dtype, "string[pyarrow]")
 
+
 @pytest.mark.parametrize(
     "dtype1,dtype2",
     [
@@ -150,6 +152,7 @@ def test_pyarrow_string_import_error(name, dtype):
 def test_dtype_equal_strict(dtype1, dtype2):
     assert not com.is_dtype_equal(dtype1, dtype2)
 
+
 def get_is_dtype_funcs():
     """
     Get all functions in pandas.core.dtypes.common that

From 9566360389c1dbd01442936508dd0ef5085dabe3 Mon Sep 17 00:00:00 2001
From: shubham11941140 <63910248+shubham11941140@users.noreply.github.com>
Date: Fri, 26 Nov 2021 16:13:22 +0530
Subject: [PATCH 12/19] StringDtype added

---
 pandas/core/dtypes/common.py       | 4 +++-
 pandas/tests/dtypes/test_common.py | 1 +
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/pandas/core/dtypes/common.py b/pandas/core/dtypes/common.py
index 6b5c0d7ce66de..8fb45f8900018 100644
--- a/pandas/core/dtypes/common.py
+++ b/pandas/core/dtypes/common.py
@@ -596,7 +596,9 @@ def is_dtype_equal(source, target) -> bool:
     False
     """
     if isinstance(target, str):
-        if not isinstance(source, str):
+        if get_dtype(source) == "string":
+            return False
+        elif not isinstance(source, str):
             # GH#38516 ensure we get the same behavior from
             #  is_dtype_equal(CDT, "category") and CDT == "category"
             # GH-44276 ensures behaviour is consistent
diff --git a/pandas/tests/dtypes/test_common.py b/pandas/tests/dtypes/test_common.py
index 4865815e99187..3578021588513 100644
--- a/pandas/tests/dtypes/test_common.py
+++ b/pandas/tests/dtypes/test_common.py
@@ -115,6 +115,7 @@ def test_period_dtype(self, dtype):
     "float": np.dtype(np.float64),
     "object": np.dtype(object),
     "category": com.pandas_dtype("category"),
+    "string": pd.StringDtype(),
 }
 
 

From 0f3554177e540a6ab1915905ed2a826d35684fe4 Mon Sep 17 00:00:00 2001
From: shubham11941140 <63910248+shubham11941140@users.noreply.github.com>
Date: Wed, 8 Dec 2021 09:06:07 +0530
Subject: [PATCH 13/19] Try-Except Changed

---
 pandas/core/dtypes/common.py | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/pandas/core/dtypes/common.py b/pandas/core/dtypes/common.py
index 8fb45f8900018..2c9a1d7b63c88 100644
--- a/pandas/core/dtypes/common.py
+++ b/pandas/core/dtypes/common.py
@@ -596,9 +596,7 @@ def is_dtype_equal(source, target) -> bool:
     False
     """
     if isinstance(target, str):
-        if get_dtype(source) == "string":
-            return False
-        elif not isinstance(source, str):
+        if not isinstance(source, str):
             # GH#38516 ensure we get the same behavior from
             #  is_dtype_equal(CDT, "category") and CDT == "category"
             # GH-44276 ensures behaviour is consistent
@@ -607,7 +605,7 @@ def is_dtype_equal(source, target) -> bool:
                 src = get_dtype(source)
                 if isinstance(src, (ExtensionDtype, np.dtype)):
 
-                    return src == target
+                    return type(src) == type(target)
             except (TypeError, AttributeError):
                 return False
     elif isinstance(source, str):

From 7ea6b154bafaf949098c51d633e4f82782368192 Mon Sep 17 00:00:00 2001
From: shubham11941140 <63910248+shubham11941140@users.noreply.github.com>
Date: Wed, 8 Dec 2021 13:44:21 +0530
Subject: [PATCH 14/19] Changes Done

---
 doc/source/whatsnew/v1.4.0.rst | 2 +-
 pandas/core/dtypes/common.py   | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/doc/source/whatsnew/v1.4.0.rst b/doc/source/whatsnew/v1.4.0.rst
index 7942b53b3ff33..ebd5d98be15fc 100644
--- a/doc/source/whatsnew/v1.4.0.rst
+++ b/doc/source/whatsnew/v1.4.0.rst
@@ -509,7 +509,7 @@ Conversion
 
 Strings
 ^^^^^^^
-- Fixed bug in :bug:`is_dtype_equal` raising if pyarrow not installed (:issue:`44327`)
+- Fixed bug in :bug:`string[pyarrow]` dtype incorrectly raising an Import Error when pyarrow is not installed (:issue:`44327`)
 -
 
 Interval
diff --git a/pandas/core/dtypes/common.py b/pandas/core/dtypes/common.py
index 2c9a1d7b63c88..705e3a7881e6d 100644
--- a/pandas/core/dtypes/common.py
+++ b/pandas/core/dtypes/common.py
@@ -605,8 +605,8 @@ def is_dtype_equal(source, target) -> bool:
                 src = get_dtype(source)
                 if isinstance(src, (ExtensionDtype, np.dtype)):
 
-                    return type(src) == type(target)
-            except (TypeError, AttributeError):
+                    return src == target
+            except (TypeError, AttributeError, ImportError):
                 return False
     elif isinstance(source, str):
         return is_dtype_equal(target, source)

From b0a75fc9f5fececd38555e30b758b980d58b2c7e Mon Sep 17 00:00:00 2001
From: Joris Van den Bossche <jorisvandenbossche@gmail.com>
Date: Tue, 14 Dec 2021 14:32:17 +0100
Subject: [PATCH 15/19] remove np.dtype from isinstance check

---
 pandas/core/dtypes/common.py | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/pandas/core/dtypes/common.py b/pandas/core/dtypes/common.py
index 6fc99f08475fa..e5657e42838a7 100644
--- a/pandas/core/dtypes/common.py
+++ b/pandas/core/dtypes/common.py
@@ -609,11 +609,9 @@ def is_dtype_equal(source, target) -> bool:
         if not isinstance(source, str):
             # GH#38516 ensure we get the same behavior from
             #  is_dtype_equal(CDT, "category") and CDT == "category"
-            # GH-44276 ensures behaviour is consistent
-            # is_dtype_equal (dtype, "string[pyarrow]")
             try:
                 src = get_dtype(source)
-                if isinstance(src, (ExtensionDtype, np.dtype)):
+                if isinstance(src, ExtensionDtype):
 
                     return src == target
             except (TypeError, AttributeError, ImportError):

From 75a4b26f7661fc6319408df7f8c69eab144200eb Mon Sep 17 00:00:00 2001
From: Joris Van den Bossche <jorisvandenbossche@gmail.com>
Date: Tue, 14 Dec 2021 14:33:09 +0100
Subject: [PATCH 16/19] remove np.dtype from isinstance check, catch
 ImportError instead

---
 pandas/core/dtypes/common.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pandas/core/dtypes/common.py b/pandas/core/dtypes/common.py
index e5657e42838a7..83a32f1abbf9a 100644
--- a/pandas/core/dtypes/common.py
+++ b/pandas/core/dtypes/common.py
@@ -623,7 +623,7 @@ def is_dtype_equal(source, target) -> bool:
         source = get_dtype(source)
         target = get_dtype(target)
         return source == target
-    except (TypeError, AttributeError):
+    except (TypeError, AttributeError, ImportError):
 
         # invalid comparison
         # object == category will hit this

From f5bedc6ac60ee589377d290f1eec5f86145e9d54 Mon Sep 17 00:00:00 2001
From: Joris Van den Bossche <jorisvandenbossche@gmail.com>
Date: Tue, 14 Dec 2021 14:34:51 +0100
Subject: [PATCH 17/19] update whatsnew

---
 doc/source/whatsnew/v1.4.0.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/doc/source/whatsnew/v1.4.0.rst b/doc/source/whatsnew/v1.4.0.rst
index a8e30bafe8d5c..bfd17089936b8 100644
--- a/doc/source/whatsnew/v1.4.0.rst
+++ b/doc/source/whatsnew/v1.4.0.rst
@@ -655,7 +655,7 @@ Conversion
 
 Strings
 ^^^^^^^
-- Fixed bug in :bug:`string[pyarrow]` dtype incorrectly raising an Import Error when pyarrow is not installed (:issue:`44327`)
+- Fixed bug in checking for :bug:`string[pyarrow]` dtype incorrectly raising an ImportError when pyarrow is not installed (:issue:`44327`)
 -
 
 Interval

From 9c68f5cdb349a3f1f4a1715241dbb73a463f98f3 Mon Sep 17 00:00:00 2001
From: Joris Van den Bossche <jorisvandenbossche@gmail.com>
Date: Tue, 14 Dec 2021 15:56:51 +0100
Subject: [PATCH 18/19] fix rst syntax in whatsnew

---
 doc/source/whatsnew/v1.4.0.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/doc/source/whatsnew/v1.4.0.rst b/doc/source/whatsnew/v1.4.0.rst
index bfd17089936b8..1765b22dda05f 100644
--- a/doc/source/whatsnew/v1.4.0.rst
+++ b/doc/source/whatsnew/v1.4.0.rst
@@ -655,7 +655,7 @@ Conversion
 
 Strings
 ^^^^^^^
-- Fixed bug in checking for :bug:`string[pyarrow]` dtype incorrectly raising an ImportError when pyarrow is not installed (:issue:`44327`)
+- Fixed bug in checking for ``string[pyarrow]`` dtype incorrectly raising an ImportError when pyarrow is not installed (:issue:`44327`)
 -
 
 Interval

From c550a004507315b7bcd50d982e421c045b674fd3 Mon Sep 17 00:00:00 2001
From: Joris Van den Bossche <jorisvandenbossche@gmail.com>
Date: Tue, 14 Dec 2021 17:09:43 +0100
Subject: [PATCH 19/19] clean-up

---
 pandas/core/dtypes/common.py | 1 -
 1 file changed, 1 deletion(-)

diff --git a/pandas/core/dtypes/common.py b/pandas/core/dtypes/common.py
index 83a32f1abbf9a..75689b8dba8f5 100644
--- a/pandas/core/dtypes/common.py
+++ b/pandas/core/dtypes/common.py
@@ -612,7 +612,6 @@ def is_dtype_equal(source, target) -> bool:
             try:
                 src = get_dtype(source)
                 if isinstance(src, ExtensionDtype):
-
                     return src == target
             except (TypeError, AttributeError, ImportError):
                 return False