From 5c90b481ace60ca803bf3e4498dd3f1e1a1f5130 Mon Sep 17 00:00:00 2001
From: Luis Obis <luis.antonio.obis@gmail.com>
Date: Mon, 24 Oct 2022 14:11:13 +0200
Subject: [PATCH 01/30] fix: initialize empty `TObject` members on
 `to_TObjString`

---
 src/uproot/writing/identify.py | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/uproot/writing/identify.py b/src/uproot/writing/identify.py
index 837edc022..322faf6f2 100644
--- a/src/uproot/writing/identify.py
+++ b/src/uproot/writing/identify.py
@@ -735,12 +735,16 @@ def to_TObjString(string):
     This function is for developers to create TObjString objects that can be
     written to ROOT files, to implement conversion routines.
     """
+    tobject = uproot.models.TObject.Model_TObject.empty()
+    tobject._members["@fUniqueID"] = 0
+    tobject._members["@fBits"] = 0
+
     tobjstring = uproot.models.TObjString.Model_TObjString(str(string))
     tobjstring._deeply_writable = True
     tobjstring._cursor = None
     tobjstring._parent = None
     tobjstring._members = {}
-    tobjstring._bases = (uproot.models.TObject.Model_TObject(),)
+    tobjstring._bases = [tobject]
     tobjstring._num_bytes = len(string) + (1 if len(string) < 255 else 5) + 16
     tobjstring._instance_version = 1
     return tobjstring

From a3d9c6a6b9b2a4f834ed40ee0f9dcf9dfccb0fbd Mon Sep 17 00:00:00 2001
From: Luis Obis <luis.antonio.obis@gmail.com>
Date: Mon, 24 Oct 2022 16:33:38 +0200
Subject: [PATCH 02/30] add test for serialization of `TObjString`

---
 tests/test_0349-write-TObjString.py | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/tests/test_0349-write-TObjString.py b/tests/test_0349-write-TObjString.py
index 0f04eaef5..0d32aecb5 100644
--- a/tests/test_0349-write-TObjString.py
+++ b/tests/test_0349-write-TObjString.py
@@ -78,3 +78,19 @@ def test_update(tmp_path):
         assert f6["subdir/wowie"] == "wowie"
         assert f6["subdir/zowie"] == "zowie"
         assert list(f6.file.streamers) == ["TObjString"]
+
+
+def test_serialization(tmp_path):
+    filename = os.path.join(tmp_path, "whatever.root")
+
+    string = "hey"
+    tobjstring = uproot.writing.identify.to_TObjString(string)
+    assert tobjstring.tojson()["_typename"] == "TObjString"  # https://github.com/scikit-hep/uproot5/issues/762
+
+    with uproot.recreate(filename) as f1:
+        f1["first"] = tobjstring
+        f1["second"] = str(tobjstring)  # also checks conversion to "str"
+
+    with uproot.open(filename) as f2:
+        assert f2["first"] == f2["second"]
+        assert str(f2["first"]) == string

From 1419d06bdd468de9e668bc340fbcd61f712b0125 Mon Sep 17 00:00:00 2001
From: Luis Obis <luis.antonio.obis@gmail.com>
Date: Mon, 24 Oct 2022 16:34:12 +0200
Subject: [PATCH 03/30] remove unused dependency on test

---
 tests/test_0349-write-TObjString.py | 1 -
 1 file changed, 1 deletion(-)

diff --git a/tests/test_0349-write-TObjString.py b/tests/test_0349-write-TObjString.py
index 0d32aecb5..097c91738 100644
--- a/tests/test_0349-write-TObjString.py
+++ b/tests/test_0349-write-TObjString.py
@@ -2,7 +2,6 @@
 
 import os
 
-import numpy as np
 import pytest
 
 import uproot

From 149a27b1d536a77629a59405c9797d32e8265e97 Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Mon, 24 Oct 2022 14:35:10 +0000
Subject: [PATCH 04/30] [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci
---
 tests/test_0349-write-TObjString.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/tests/test_0349-write-TObjString.py b/tests/test_0349-write-TObjString.py
index 097c91738..d036c194e 100644
--- a/tests/test_0349-write-TObjString.py
+++ b/tests/test_0349-write-TObjString.py
@@ -84,7 +84,9 @@ def test_serialization(tmp_path):
 
     string = "hey"
     tobjstring = uproot.writing.identify.to_TObjString(string)
-    assert tobjstring.tojson()["_typename"] == "TObjString"  # https://github.com/scikit-hep/uproot5/issues/762
+    assert (
+        tobjstring.tojson()["_typename"] == "TObjString"
+    )  # https://github.com/scikit-hep/uproot5/issues/762
 
     with uproot.recreate(filename) as f1:
         f1["first"] = tobjstring

From 8209f7237f377dfd8a15932662a1c396d1abce42 Mon Sep 17 00:00:00 2001
From: Luis Obis <luis.antonio.obis@gmail.com>
Date: Mon, 24 Oct 2022 20:11:31 +0200
Subject: [PATCH 05/30] add `tojson` method to `TObjString`

---
 src/uproot/models/TObjString.py | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/uproot/models/TObjString.py b/src/uproot/models/TObjString.py
index 544dc7faf..f51aaede7 100644
--- a/src/uproot/models/TObjString.py
+++ b/src/uproot/models/TObjString.py
@@ -64,6 +64,12 @@ def fTitle(self):
 
     writable = True
 
+    def tojson(self):
+        out = self._bases[0].tojson()  # TObject
+        out["_typename"] = self.classname
+        out["fString"] = str(self)
+        return out
+
     def _serialize(self, out, header, name, tobject_flags):
         where = len(out)
         for x in self._bases:

From a30e8e1bcff10626a2db76c5814e16a54e74a17c Mon Sep 17 00:00:00 2001
From: Luis Obis <luis.antonio.obis@gmail.com>
Date: Mon, 24 Oct 2022 20:53:20 +0200
Subject: [PATCH 06/30] add additional check to `TObjString` write test

---
 tests/test_0349-write-TObjString.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tests/test_0349-write-TObjString.py b/tests/test_0349-write-TObjString.py
index d036c194e..b1ee83651 100644
--- a/tests/test_0349-write-TObjString.py
+++ b/tests/test_0349-write-TObjString.py
@@ -87,6 +87,7 @@ def test_serialization(tmp_path):
     assert (
         tobjstring.tojson()["_typename"] == "TObjString"
     )  # https://github.com/scikit-hep/uproot5/issues/762
+    assert tobjstring.tojson()["fString"] == str(tobjstring)
 
     with uproot.recreate(filename) as f1:
         f1["first"] = tobjstring

From 4c828c80ffc4fccb7b9da88dd67deed84aa71e5f Mon Sep 17 00:00:00 2001
From: Luis Obis <luis.antonio.obis@gmail.com>
Date: Mon, 24 Oct 2022 20:55:16 +0200
Subject: [PATCH 07/30] fix bad field in `TList` tojson conversion

---
 src/uproot/models/TList.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/uproot/models/TList.py b/src/uproot/models/TList.py
index 0990e3259..43dc1ae8c 100644
--- a/src/uproot/models/TList.py
+++ b/src/uproot/models/TList.py
@@ -81,7 +81,7 @@ def tojson(self):
             "_typename": "TList",
             "name": "TList",
             "arr": [x.tojson() for x in self._data],
-            "opt": [],
+            "opt": ["" for _ in self._data],
         }
 
     writable = True

From 5c95c4b78e29fb98ffaac3b400777c7bcf6764df Mon Sep 17 00:00:00 2001
From: Luis Obis <luis.antonio.obis@gmail.com>
Date: Mon, 24 Oct 2022 21:04:12 +0200
Subject: [PATCH 08/30] add inexpensive `assert` to `TList` serialization

---
 src/uproot/models/TList.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/uproot/models/TList.py b/src/uproot/models/TList.py
index 43dc1ae8c..7b638ac4d 100644
--- a/src/uproot/models/TList.py
+++ b/src/uproot/models/TList.py
@@ -91,6 +91,8 @@ def _to_writable_postprocess(self, original):
         self._options = original._options
 
     def _serialize(self, out, header, name, tobject_flags):
+        assert self._members["fSize"] == len(self._data) == len(self._options), "Fatal error in TList serialization."
+
         import uproot.writing._cascade
 
         where = len(out)

From 163c8a20432c1ad9585a1cc361248e80c3f8e156 Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Mon, 24 Oct 2022 19:28:53 +0000
Subject: [PATCH 09/30] [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci
---
 src/uproot/models/TList.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/uproot/models/TList.py b/src/uproot/models/TList.py
index 7b638ac4d..8223c3157 100644
--- a/src/uproot/models/TList.py
+++ b/src/uproot/models/TList.py
@@ -91,7 +91,9 @@ def _to_writable_postprocess(self, original):
         self._options = original._options
 
     def _serialize(self, out, header, name, tobject_flags):
-        assert self._members["fSize"] == len(self._data) == len(self._options), "Fatal error in TList serialization."
+        assert (
+            self._members["fSize"] == len(self._data) == len(self._options)
+        ), "Fatal error in TList serialization."
 
         import uproot.writing._cascade
 

From 4da653fee0f28789fbb20abcad3a4541acd6701a Mon Sep 17 00:00:00 2001
From: Luis Obis <luis.antonio.obis@gmail.com>
Date: Tue, 25 Oct 2022 12:08:49 +0200
Subject: [PATCH 10/30] fix bad serialization of non-empty TList due to options
 (https://github.com/scikit-hep/uproot5/pull/763#issuecomment-1290149135)

---
 src/uproot/writing/identify.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/uproot/writing/identify.py b/src/uproot/writing/identify.py
index 322faf6f2..8dd459e13 100644
--- a/src/uproot/writing/identify.py
+++ b/src/uproot/writing/identify.py
@@ -773,7 +773,8 @@ def to_TList(data, name=""):
     tlist._members["fName"] = name
     tlist._data = list(data)
     tlist._members["fSize"] = len(tlist._data)
-    tlist._options = [b""] * len(tlist._data)
+    # see https://github.com/scikit-hep/uproot5/pull/763#issuecomment-1290149135
+    tlist._options = [uproot.serialization.string("")] * len(tlist._data)
 
     if all(x._deeply_writable for x in tlist._data):
         tlist._deeply_writable = True

From db3595446c4c79d2fcd6bb5e17c180d9d7937bcb Mon Sep 17 00:00:00 2001
From: Luis Obis <luis.antonio.obis@gmail.com>
Date: Tue, 25 Oct 2022 12:30:03 +0200
Subject: [PATCH 11/30] add tests for TList serialization

---
 tests/test_0351-write-TList.py | 58 ++++++++++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)
 create mode 100644 tests/test_0351-write-TList.py

diff --git a/tests/test_0351-write-TList.py b/tests/test_0351-write-TList.py
new file mode 100644
index 000000000..091b98837
--- /dev/null
+++ b/tests/test_0351-write-TList.py
@@ -0,0 +1,58 @@
+# BSD 3-Clause License; see https://github.com/scikit-hep/uproot4/blob/main/LICENSE
+
+import os
+
+import pytest
+
+import uproot
+import uproot.writing
+
+
+def test_write_empty(tmp_path):
+    filename = os.path.join(tmp_path, "whatever.root")
+
+    tlist = uproot.writing.identify.to_TList([])
+
+    with uproot.recreate(filename) as f:
+        f["test"] = tlist
+
+    with uproot.open(filename) as f2:
+        assert len(f2["test"]) == 0
+
+
+def test_write_single_key(tmp_path):
+    filename = os.path.join(tmp_path, "whatever.root")
+
+    tlist = uproot.writing.identify.to_TList([uproot.writing.identify.to_TObjString("test string")])
+
+    with uproot.recreate(filename) as f:
+        f["test"] = tlist
+
+    with uproot.open(filename) as f2:
+        assert len(f2["test"]) == 1
+
+
+def test_write_nested(tmp_path):
+    filename = os.path.join(tmp_path, "whatever.root")
+
+    tlist_child = uproot.writing.identify.to_TList(
+        [uproot.writing.identify.to_TObjString(s) for s in "this is a test".split()])
+
+    entries = [uproot.writing.identify.to_TObjString("this string goes in the front"), tlist_child,
+               uproot.writing.identify.to_TObjString("test string")]
+
+    tlist = uproot.writing.identify.to_TList(entries)
+
+    with uproot.recreate(filename) as f:
+        f["test"] = tlist
+
+    with uproot.open(filename) as f2:
+        parent_list = f2["test"]
+        assert len(parent_list) == 3
+        assert isinstance(parent_list[0], uproot.models.TObjString.Model_TObjString)
+        assert str(parent_list[0]) == "this string goes in the front"
+        assert str(parent_list[2]) == "test string"
+        child_list = parent_list[1]
+        assert isinstance(child_list, uproot.models.TList.Model_TList)
+        assert len(child_list) == 4
+        assert " ".join([str(s) for s in child_list]) == "this is a test"

From 5fff9ddc05bd1ae1d6f71cb8b79822fbce70c23b Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Tue, 25 Oct 2022 10:31:31 +0000
Subject: [PATCH 12/30] [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci
---
 tests/test_0351-write-TList.py | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/tests/test_0351-write-TList.py b/tests/test_0351-write-TList.py
index 091b98837..2355b5b84 100644
--- a/tests/test_0351-write-TList.py
+++ b/tests/test_0351-write-TList.py
@@ -23,7 +23,9 @@ def test_write_empty(tmp_path):
 def test_write_single_key(tmp_path):
     filename = os.path.join(tmp_path, "whatever.root")
 
-    tlist = uproot.writing.identify.to_TList([uproot.writing.identify.to_TObjString("test string")])
+    tlist = uproot.writing.identify.to_TList(
+        [uproot.writing.identify.to_TObjString("test string")]
+    )
 
     with uproot.recreate(filename) as f:
         f["test"] = tlist
@@ -36,10 +38,14 @@ def test_write_nested(tmp_path):
     filename = os.path.join(tmp_path, "whatever.root")
 
     tlist_child = uproot.writing.identify.to_TList(
-        [uproot.writing.identify.to_TObjString(s) for s in "this is a test".split()])
-
-    entries = [uproot.writing.identify.to_TObjString("this string goes in the front"), tlist_child,
-               uproot.writing.identify.to_TObjString("test string")]
+        [uproot.writing.identify.to_TObjString(s) for s in "this is a test".split()]
+    )
+
+    entries = [
+        uproot.writing.identify.to_TObjString("this string goes in the front"),
+        tlist_child,
+        uproot.writing.identify.to_TObjString("test string"),
+    ]
 
     tlist = uproot.writing.identify.to_TList(entries)
 

From bc95096d78e145e170c05c7bdd56f779d7c08df7 Mon Sep 17 00:00:00 2001
From: Luis Obis <luis.antonio.obis@gmail.com>
Date: Tue, 25 Oct 2022 12:36:53 +0200
Subject: [PATCH 13/30] fixed bad `__repr__` for `TObject`

---
 src/uproot/models/TObject.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/uproot/models/TObject.py b/src/uproot/models/TObject.py
index 5e5617b41..36230d56d 100644
--- a/src/uproot/models/TObject.py
+++ b/src/uproot/models/TObject.py
@@ -114,7 +114,7 @@ def awkward_form(cls, file, context):
 
     def __repr__(self):
         return "<TObject {} {} at 0x{:012x}>".format(
-            self._members.get("fUniqueID"), self._members.get("fBits"), id(self)
+            self.member("@fUniqueID"), self.member("@fBits"), id(self)
         )
 
     def tojson(self):

From 6697fa093d79f2b2ab79b8e2effef7f2630949a5 Mon Sep 17 00:00:00 2001
From: Luis Obis <luis.antonio.obis@gmail.com>
Date: Tue, 25 Oct 2022 12:38:38 +0200
Subject: [PATCH 14/30] add serialization of `fUniqueID` to `TObject`

---
 src/uproot/models/TObject.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/uproot/models/TObject.py b/src/uproot/models/TObject.py
index 36230d56d..2a37ba8cf 100644
--- a/src/uproot/models/TObject.py
+++ b/src/uproot/models/TObject.py
@@ -69,7 +69,7 @@ def read_members(self, chunk, cursor, context, file):
     writable = True
 
     def _serialize(self, out, header, name, tobject_flags):
-        out.append(b"\x00\x01" + _tobject_format2.pack(0, tobject_flags))
+        out.append(b"\x00\x01" + _tobject_format2.pack(self.member("@fUniqueID"), tobject_flags))
 
     @classmethod
     def strided_interpretation(

From 94e93a8c33c40eb5c8dcb5c66167ff0710aa78f9 Mon Sep 17 00:00:00 2001
From: Luis Obis <luis.antonio.obis@gmail.com>
Date: Tue, 25 Oct 2022 13:48:45 +0200
Subject: [PATCH 15/30] add `empty` method to `TObject`

---
 src/uproot/models/TObject.py | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/uproot/models/TObject.py b/src/uproot/models/TObject.py
index 2a37ba8cf..57219d27e 100644
--- a/src/uproot/models/TObject.py
+++ b/src/uproot/models/TObject.py
@@ -124,5 +124,13 @@ def tojson(self):
             "fBits": self.member("@fBits"),
         }
 
+    @classmethod
+    def empty(cls):
+        self = uproot.model.Model.empty()
+        self.__class__ = cls
+        self._members["@fUniqueID"] = 0
+        self._members["@fBits"] = 0
+        return self
+
 
 uproot.classes["TObject"] = Model_TObject

From 46424e1057546ebfd1f1674ef2ba80ab54a6c412 Mon Sep 17 00:00:00 2001
From: Luis Obis <luis.antonio.obis@gmail.com>
Date: Tue, 25 Oct 2022 13:50:12 +0200
Subject: [PATCH 16/30] remove redundant `TObject` member initialization

---
 src/uproot/writing/identify.py | 8 --------
 1 file changed, 8 deletions(-)

diff --git a/src/uproot/writing/identify.py b/src/uproot/writing/identify.py
index 8dd459e13..8b7b88c9b 100644
--- a/src/uproot/writing/identify.py
+++ b/src/uproot/writing/identify.py
@@ -736,8 +736,6 @@ def to_TObjString(string):
     written to ROOT files, to implement conversion routines.
     """
     tobject = uproot.models.TObject.Model_TObject.empty()
-    tobject._members["@fUniqueID"] = 0
-    tobject._members["@fBits"] = 0
 
     tobjstring = uproot.models.TObjString.Model_TObjString(str(string))
     tobjstring._deeply_writable = True
@@ -765,8 +763,6 @@ def to_TList(data, name=""):
         )
 
     tobject = uproot.models.TObject.Model_TObject.empty()
-    tobject._members["@fUniqueID"] = 0
-    tobject._members["@fBits"] = 0
 
     tlist = uproot.models.TList.Model_TList.empty()
     tlist._bases.append(tobject)
@@ -879,8 +875,6 @@ def to_TAxis(
     written to ROOT files, to implement conversion routines.
     """
     tobject = uproot.models.TObject.Model_TObject.empty()
-    tobject._members["@fUniqueID"] = 0
-    tobject._members["@fBits"] = 0
 
     tnamed = uproot.models.TNamed.Model_TNamed.empty()
     tnamed._deeply_writable = True
@@ -1023,8 +1017,6 @@ def to_TH1x(
     TH1C, TH1D, TH1F, TH1I, or TH1S depends on the dtype of the ``data`` array.
     """
     tobject = uproot.models.TObject.Model_TObject.empty()
-    tobject._members["@fUniqueID"] = 0
-    tobject._members["@fBits"] = 0
 
     tnamed = uproot.models.TNamed.Model_TNamed.empty()
     tnamed._deeply_writable = True

From 6b1f1883a4526aaee3690f3349026cc4dc965fa5 Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Tue, 25 Oct 2022 11:51:25 +0000
Subject: [PATCH 17/30] [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci
---
 src/uproot/models/TObject.py | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/uproot/models/TObject.py b/src/uproot/models/TObject.py
index 57219d27e..92c43ea69 100644
--- a/src/uproot/models/TObject.py
+++ b/src/uproot/models/TObject.py
@@ -69,7 +69,10 @@ def read_members(self, chunk, cursor, context, file):
     writable = True
 
     def _serialize(self, out, header, name, tobject_flags):
-        out.append(b"\x00\x01" + _tobject_format2.pack(self.member("@fUniqueID"), tobject_flags))
+        out.append(
+            b"\x00\x01"
+            + _tobject_format2.pack(self.member("@fUniqueID"), tobject_flags)
+        )
 
     @classmethod
     def strided_interpretation(

From 303514d30f18ca4c420f545d6b1facd5097d69d3 Mon Sep 17 00:00:00 2001
From: Luis Antonio Obis Aparicio <35803280+lobis@users.noreply.github.com>
Date: Tue, 25 Oct 2022 23:07:09 +0200
Subject: [PATCH 18/30] Update src/uproot/writing/identify.py

Co-authored-by: Jim Pivarski <jpivarski@users.noreply.github.com>
---
 src/uproot/writing/identify.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/uproot/writing/identify.py b/src/uproot/writing/identify.py
index 8b7b88c9b..8fc9d01a8 100644
--- a/src/uproot/writing/identify.py
+++ b/src/uproot/writing/identify.py
@@ -742,7 +742,7 @@ def to_TObjString(string):
     tobjstring._cursor = None
     tobjstring._parent = None
     tobjstring._members = {}
-    tobjstring._bases = [tobject]
+    tobjstring._bases = (tobject,)
     tobjstring._num_bytes = len(string) + (1 if len(string) < 255 else 5) + 16
     tobjstring._instance_version = 1
     return tobjstring

From d6e154308dee74c8a21170578e32af0f20827551 Mon Sep 17 00:00:00 2001
From: Luis Obis <luis.antonio.obis@gmail.com>
Date: Tue, 25 Oct 2022 23:29:45 +0200
Subject: [PATCH 19/30] moved `TList` serialization list to `serialize` method

---
 src/uproot/models/TList.py     | 2 +-
 src/uproot/writing/identify.py | 3 +--
 2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/src/uproot/models/TList.py b/src/uproot/models/TList.py
index 8223c3157..324860838 100644
--- a/src/uproot/models/TList.py
+++ b/src/uproot/models/TList.py
@@ -106,7 +106,7 @@ def _serialize(self, out, header, name, tobject_flags):
 
         for datum, option in zip(self._data, self._options):
             uproot.serialization._serialize_object_any(out, datum, None)
-            out.append(option)
+            out.append(uproot.serialization.string(option))
 
         if header:
             num_bytes = sum(len(x) for x in out[where:])
diff --git a/src/uproot/writing/identify.py b/src/uproot/writing/identify.py
index 8fc9d01a8..e7ac769a9 100644
--- a/src/uproot/writing/identify.py
+++ b/src/uproot/writing/identify.py
@@ -769,8 +769,7 @@ def to_TList(data, name=""):
     tlist._members["fName"] = name
     tlist._data = list(data)
     tlist._members["fSize"] = len(tlist._data)
-    # see https://github.com/scikit-hep/uproot5/pull/763#issuecomment-1290149135
-    tlist._options = [uproot.serialization.string("")] * len(tlist._data)
+    tlist._options = [""] * len(tlist._data)
 
     if all(x._deeply_writable for x in tlist._data):
         tlist._deeply_writable = True

From 0621c67a64becfa8d7e847e2af24274eb27bcac2 Mon Sep 17 00:00:00 2001
From: Luis Obis <luis.antonio.obis@gmail.com>
Date: Wed, 26 Oct 2022 01:14:23 +0200
Subject: [PATCH 20/30] add helper serialization method `bytestring` as
 suggested in
 https://github.com/scikit-hep/uproot5/pull/763#issuecomment-1290149135 by
 @agoose77

---
 src/uproot/serialization.py | 20 ++++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/src/uproot/serialization.py b/src/uproot/serialization.py
index fcfcf3c81..d4edc932a 100644
--- a/src/uproot/serialization.py
+++ b/src/uproot/serialization.py
@@ -24,12 +24,24 @@ def string(data):
     is preceded by a 1-byte length; otherwise, it is preceded by ``b'\xff'`` and a
     4-byte length.
     """
-    bytestring = data.encode(errors="surrogateescape")
-    length = len(bytestring)
+    return bytestring(
+        data.encode(errors="surrogateescape")
+    )
+
+
+def bytestring(data):
+    """
+    Converts Python bytes into a length-prefixed bytestring, ready to be written to a file.
+
+    If the string's byte representation (UTF-8) has fewer than 255 bytes, it
+    is preceded by a 1-byte length; otherwise, it is preceded by ``b'\xff'`` and a
+    4-byte length.
+    """
+    length = len(data)
     if length < 255:
-        return struct.pack(">B%ds" % length, length, bytestring)
+        return struct.pack(">B%ds" % length, length, data)
     else:
-        return struct.pack(">BI%ds" % length, 255, length, bytestring)
+        return struct.pack(">BI%ds" % length, 255, length, data)
 
 
 def numbytes_version(num_bytes, version):

From 8e6ad2e17404b9c387bfab8fe60e97b511562e7e Mon Sep 17 00:00:00 2001
From: Luis Obis <luis.antonio.obis@gmail.com>
Date: Wed, 26 Oct 2022 01:16:02 +0200
Subject: [PATCH 21/30] keep `TList` `_options` as python `bytes` and update
 serialization to use the new `bytestring` helper

---
 src/uproot/models/TList.py     | 2 +-
 src/uproot/writing/identify.py | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/uproot/models/TList.py b/src/uproot/models/TList.py
index 324860838..347b0ba45 100644
--- a/src/uproot/models/TList.py
+++ b/src/uproot/models/TList.py
@@ -106,7 +106,7 @@ def _serialize(self, out, header, name, tobject_flags):
 
         for datum, option in zip(self._data, self._options):
             uproot.serialization._serialize_object_any(out, datum, None)
-            out.append(uproot.serialization.string(option))
+            out.append(uproot.serialization.bytestring(option))
 
         if header:
             num_bytes = sum(len(x) for x in out[where:])
diff --git a/src/uproot/writing/identify.py b/src/uproot/writing/identify.py
index e7ac769a9..2a2239685 100644
--- a/src/uproot/writing/identify.py
+++ b/src/uproot/writing/identify.py
@@ -769,7 +769,7 @@ def to_TList(data, name=""):
     tlist._members["fName"] = name
     tlist._data = list(data)
     tlist._members["fSize"] = len(tlist._data)
-    tlist._options = [""] * len(tlist._data)
+    tlist._options = [b""] * len(tlist._data)
 
     if all(x._deeply_writable for x in tlist._data):
         tlist._deeply_writable = True

From 897972ff5d3730ed96c221528be9111a4eb2745e Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Tue, 25 Oct 2022 23:16:57 +0000
Subject: [PATCH 22/30] [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci
---
 src/uproot/serialization.py | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/src/uproot/serialization.py b/src/uproot/serialization.py
index d4edc932a..71218dd84 100644
--- a/src/uproot/serialization.py
+++ b/src/uproot/serialization.py
@@ -24,9 +24,7 @@ def string(data):
     is preceded by a 1-byte length; otherwise, it is preceded by ``b'\xff'`` and a
     4-byte length.
     """
-    return bytestring(
-        data.encode(errors="surrogateescape")
-    )
+    return bytestring(data.encode(errors="surrogateescape"))
 
 
 def bytestring(data):

From 9a500c14b19094d41337c678b1ba16754e1921f3 Mon Sep 17 00:00:00 2001
From: Luis Obis <luis.antonio.obis@gmail.com>
Date: Wed, 26 Oct 2022 10:37:11 +0200
Subject: [PATCH 23/30] reset `serialization.py` to `main` branch status

---
 src/uproot/serialization.py | 18 ++++--------------
 1 file changed, 4 insertions(+), 14 deletions(-)

diff --git a/src/uproot/serialization.py b/src/uproot/serialization.py
index 71218dd84..fcfcf3c81 100644
--- a/src/uproot/serialization.py
+++ b/src/uproot/serialization.py
@@ -24,22 +24,12 @@ def string(data):
     is preceded by a 1-byte length; otherwise, it is preceded by ``b'\xff'`` and a
     4-byte length.
     """
-    return bytestring(data.encode(errors="surrogateescape"))
-
-
-def bytestring(data):
-    """
-    Converts Python bytes into a length-prefixed bytestring, ready to be written to a file.
-
-    If the string's byte representation (UTF-8) has fewer than 255 bytes, it
-    is preceded by a 1-byte length; otherwise, it is preceded by ``b'\xff'`` and a
-    4-byte length.
-    """
-    length = len(data)
+    bytestring = data.encode(errors="surrogateescape")
+    length = len(bytestring)
     if length < 255:
-        return struct.pack(">B%ds" % length, length, data)
+        return struct.pack(">B%ds" % length, length, bytestring)
     else:
-        return struct.pack(">BI%ds" % length, 255, length, data)
+        return struct.pack(">BI%ds" % length, 255, length, bytestring)
 
 
 def numbytes_version(num_bytes, version):

From 884ec4de4ec22e25974d72e814b9f02b578d22c0 Mon Sep 17 00:00:00 2001
From: Luis Obis <luis.antonio.obis@gmail.com>
Date: Wed, 26 Oct 2022 10:37:53 +0200
Subject: [PATCH 24/30] Revert "keep `TList` `_options` as python `bytes` and
 update serialization to use the new `bytestring` helper"

This reverts commit 8e6ad2e17404b9c387bfab8fe60e97b511562e7e.
---
 src/uproot/models/TList.py     | 2 +-
 src/uproot/writing/identify.py | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/uproot/models/TList.py b/src/uproot/models/TList.py
index 347b0ba45..324860838 100644
--- a/src/uproot/models/TList.py
+++ b/src/uproot/models/TList.py
@@ -106,7 +106,7 @@ def _serialize(self, out, header, name, tobject_flags):
 
         for datum, option in zip(self._data, self._options):
             uproot.serialization._serialize_object_any(out, datum, None)
-            out.append(uproot.serialization.bytestring(option))
+            out.append(uproot.serialization.string(option))
 
         if header:
             num_bytes = sum(len(x) for x in out[where:])
diff --git a/src/uproot/writing/identify.py b/src/uproot/writing/identify.py
index 2a2239685..e7ac769a9 100644
--- a/src/uproot/writing/identify.py
+++ b/src/uproot/writing/identify.py
@@ -769,7 +769,7 @@ def to_TList(data, name=""):
     tlist._members["fName"] = name
     tlist._data = list(data)
     tlist._members["fSize"] = len(tlist._data)
-    tlist._options = [b""] * len(tlist._data)
+    tlist._options = [""] * len(tlist._data)
 
     if all(x._deeply_writable for x in tlist._data):
         tlist._deeply_writable = True

From 3c8b85bb57e42089340054411ce7af7bb0f72e6e Mon Sep 17 00:00:00 2001
From: Luis Obis <luis.antonio.obis@gmail.com>
Date: Wed, 26 Oct 2022 10:39:02 +0200
Subject: [PATCH 25/30] Revert "[pre-commit.ci] auto fixes from pre-commit.com
 hooks"

This reverts commit 897972ff5d3730ed96c221528be9111a4eb2745e.

# Conflicts:
#	src/uproot/serialization.py
---
 src/uproot/serialization.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/uproot/serialization.py b/src/uproot/serialization.py
index fcfcf3c81..7005f968d 100644
--- a/src/uproot/serialization.py
+++ b/src/uproot/serialization.py
@@ -80,4 +80,4 @@ def serialize_object_any(model, name=None):
     """
     out = []
     _serialize_object_any(out, model, name)
-    return b"".join(out)
+    return b"".join(out)
\ No newline at end of file

From 45720ffc1239b69b42c4720db65173657e182be8 Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Wed, 26 Oct 2022 08:41:10 +0000
Subject: [PATCH 26/30] [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci
---
 src/uproot/serialization.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/uproot/serialization.py b/src/uproot/serialization.py
index 7005f968d..fcfcf3c81 100644
--- a/src/uproot/serialization.py
+++ b/src/uproot/serialization.py
@@ -80,4 +80,4 @@ def serialize_object_any(model, name=None):
     """
     out = []
     _serialize_object_any(out, model, name)
-    return b"".join(out)
\ No newline at end of file
+    return b"".join(out)

From 6dde481ed074468c790d6759ee5b2670d3f857ea Mon Sep 17 00:00:00 2001
From: Luis Obis <luis.antonio.obis@gmail.com>
Date: Wed, 26 Oct 2022 10:43:42 +0200
Subject: [PATCH 27/30] Revert "reset `serialization.py` to `main` branch
 status"

This reverts commit 9a500c14b19094d41337c678b1ba16754e1921f3.
---
 src/uproot/serialization.py | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/src/uproot/serialization.py b/src/uproot/serialization.py
index fcfcf3c81..71218dd84 100644
--- a/src/uproot/serialization.py
+++ b/src/uproot/serialization.py
@@ -24,12 +24,22 @@ def string(data):
     is preceded by a 1-byte length; otherwise, it is preceded by ``b'\xff'`` and a
     4-byte length.
     """
-    bytestring = data.encode(errors="surrogateescape")
-    length = len(bytestring)
+    return bytestring(data.encode(errors="surrogateescape"))
+
+
+def bytestring(data):
+    """
+    Converts Python bytes into a length-prefixed bytestring, ready to be written to a file.
+
+    If the string's byte representation (UTF-8) has fewer than 255 bytes, it
+    is preceded by a 1-byte length; otherwise, it is preceded by ``b'\xff'`` and a
+    4-byte length.
+    """
+    length = len(data)
     if length < 255:
-        return struct.pack(">B%ds" % length, length, bytestring)
+        return struct.pack(">B%ds" % length, length, data)
     else:
-        return struct.pack(">BI%ds" % length, 255, length, bytestring)
+        return struct.pack(">BI%ds" % length, 255, length, data)
 
 
 def numbytes_version(num_bytes, version):

From 3eac7cafbfbfceb8afd072c714590691619ecb8a Mon Sep 17 00:00:00 2001
From: Luis Obis <luis.antonio.obis@gmail.com>
Date: Wed, 26 Oct 2022 10:43:48 +0200
Subject: [PATCH 28/30] Revert "Revert "keep `TList` `_options` as python
 `bytes` and update serialization to use the new `bytestring` helper""

This reverts commit 884ec4de4ec22e25974d72e814b9f02b578d22c0.
---
 src/uproot/models/TList.py     | 2 +-
 src/uproot/writing/identify.py | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/uproot/models/TList.py b/src/uproot/models/TList.py
index 324860838..347b0ba45 100644
--- a/src/uproot/models/TList.py
+++ b/src/uproot/models/TList.py
@@ -106,7 +106,7 @@ def _serialize(self, out, header, name, tobject_flags):
 
         for datum, option in zip(self._data, self._options):
             uproot.serialization._serialize_object_any(out, datum, None)
-            out.append(uproot.serialization.string(option))
+            out.append(uproot.serialization.bytestring(option))
 
         if header:
             num_bytes = sum(len(x) for x in out[where:])
diff --git a/src/uproot/writing/identify.py b/src/uproot/writing/identify.py
index e7ac769a9..2a2239685 100644
--- a/src/uproot/writing/identify.py
+++ b/src/uproot/writing/identify.py
@@ -769,7 +769,7 @@ def to_TList(data, name=""):
     tlist._members["fName"] = name
     tlist._data = list(data)
     tlist._members["fSize"] = len(tlist._data)
-    tlist._options = [""] * len(tlist._data)
+    tlist._options = [b""] * len(tlist._data)
 
     if all(x._deeply_writable for x in tlist._data):
         tlist._deeply_writable = True

From cb6deb7d21fa0ab1f2933a37dd48fef2c6b28dd8 Mon Sep 17 00:00:00 2001
From: Luis Antonio Obis Aparicio <35803280+lobis@users.noreply.github.com>
Date: Thu, 27 Oct 2022 09:38:19 +0200
Subject: [PATCH 29/30] Update src/uproot/models/TObject.py

Co-authored-by: Angus Hollands <goosey15@gmail.com>
---
 src/uproot/models/TObject.py | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/uproot/models/TObject.py b/src/uproot/models/TObject.py
index 8af4a3eb0..2016df227 100644
--- a/src/uproot/models/TObject.py
+++ b/src/uproot/models/TObject.py
@@ -129,8 +129,7 @@ def tojson(self):
 
     @classmethod
     def empty(cls):
-        self = uproot.model.Model.empty()
-        self.__class__ = cls
+        self = super(Model_TObject, cls).empty()
         self._members["@fUniqueID"] = 0
         self._members["@fBits"] = 0
         return self

From 2d6917490b86a7cb89884d5b08e9bcb7ac0424e1 Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Thu, 27 Oct 2022 07:38:53 +0000
Subject: [PATCH 30/30] [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci
---
 src/uproot/models/TObject.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/uproot/models/TObject.py b/src/uproot/models/TObject.py
index 2016df227..1303e60b5 100644
--- a/src/uproot/models/TObject.py
+++ b/src/uproot/models/TObject.py
@@ -129,7 +129,7 @@ def tojson(self):
 
     @classmethod
     def empty(cls):
-        self = super(Model_TObject, cls).empty()
+        self = super().empty()
         self._members["@fUniqueID"] = 0
         self._members["@fBits"] = 0
         return self