diff --git a/python-fonttools.spec b/python-fonttools.spec
index cb699ea..f0245c7 100644
--- a/python-fonttools.spec
+++ b/python-fonttools.spec
@@ -1,10 +1,12 @@
 Name:           fonttools
 Version:        3.29.0
-Release:        5
+Release:        6
 Summary:        Tools to manipulate font files
 License:        MIT
 URL:            https://github.com/fonttools/fonttools/
 Source0:        %{url}/releases/download/%{version}/fonttools-%{version}.zip
+Patch01:	replace-fromtring-with-frombytes.patch
+Patch02:	replace-totring-with-tobytes.patch
 Requires:       python3-fonttools
 BuildArch:      noarch
 Provides:       ttx = %{version}-%{release}
@@ -62,6 +64,10 @@ rm -rf *.egg-info
 %{python3_sitelib}/fonttools-%{version}-py3.*.egg-info
 
 %changelog
+* Wed Apr 06 2022 houyingchao <houyingchao@h-partners.com> - 3.29.0-6
+- Replace totring with tobytes
+- Replace fromtring with frombytes
+
 * Wed Mar 30 2022 baizhonggui <baizhonggui@huawei.com> - 3.29.0-5
 - support py3.10+ wildcard to fix build error
 
diff --git a/replace-fromtring-with-frombytes.patch b/replace-fromtring-with-frombytes.patch
new file mode 100644
index 0000000..d0653ab
--- /dev/null
+++ b/replace-fromtring-with-frombytes.patch
@@ -0,0 +1,331 @@
+From 12814aa7b174428ef7c2baf83411b12fef921e0b Mon Sep 17 00:00:00 2001
+From: Chris Simpkins <git.simpkins@gmail.com>
+Date: Thu, 29 Aug 2019 22:58:42 -0400
+Subject: [PATCH] refactor array.fromstring to array.frombytes
+
+fromstring is a deprecated array method
+---
+ Lib/fontTools/designspaceLib/__init__.py     |  2 +-
+ Lib/fontTools/svgLib/path/__init__.py        |  8 ++++----
+ Lib/fontTools/ttLib/tables/G_P_K_G_.py       |  4 ++--
+ Lib/fontTools/ttLib/tables/G__l_o_c.py       |  4 ++--
+ Lib/fontTools/ttLib/tables/L_T_S_H_.py       |  2 +-
+ Lib/fontTools/ttLib/tables/T_S_I__5.py       |  2 +-
+ Lib/fontTools/ttLib/tables/TupleVariation.py |  4 ++--
+ Lib/fontTools/ttLib/tables/_c_m_a_p.py       | 10 +++++-----
+ Lib/fontTools/ttLib/tables/_c_v_t.py         |  2 +-
+ Lib/fontTools/ttLib/tables/_g_l_y_f.py       |  2 +-
+ Lib/fontTools/ttLib/tables/_g_v_a_r.py       |  2 +-
+ Lib/fontTools/ttLib/tables/_l_o_c_a.py       |  2 +-
+ Lib/fontTools/ttLib/tables/_p_o_s_t.py       |  4 ++--
+ Lib/fontTools/varLib/designspace.py          |  2 +-
+ Snippets/svg2glif.py                         |  2 +-
+ Tests/svgLib/path/path_test.py               |  6 +++---
+ 16 files changed, 29 insertions(+), 29 deletions(-)
+
+diff --git a/Lib/fontTools/designspaceLib/__init__.py b/Lib/fontTools/designspaceLib/__init__.py
+index 8063ac5..72a4cee 100644
+--- a/Lib/fontTools/designspaceLib/__init__.py
++++ b/Lib/fontTools/designspaceLib/__init__.py
+@@ -38,7 +38,7 @@ def to_plist(value):
+     except AttributeError:
+         # Python 3
+         string = plistlib.dumps(value).decode()
+-    return ET.fromstring(string)[0]
++    return ET.frombytes(string)[0]
+ 
+ 
+ def from_plist(element):
+diff --git a/Lib/fontTools/svgLib/path/__init__.py b/Lib/fontTools/svgLib/path/__init__.py
+index 4f17e76..a18abd9 100644
+--- a/Lib/fontTools/svgLib/path/__init__.py
++++ b/Lib/fontTools/svgLib/path/__init__.py
+@@ -27,10 +27,10 @@ class SVGPath(object):
+         svg.draw(pen)
+ 
+     Or reading from a string containing SVG data, using the alternative
+-    'fromstring' (a class method):
++    'frombytes' (a class method):
+ 
+         data = '<?xml version="1.0" ...'
+-        svg = SVGPath.fromstring(data)
++        svg = SVGPath.frombytes(data)
+         svg.draw(pen)
+ 
+     Both constructors can optionally take a 'transform' matrix (6-float
+@@ -46,9 +46,9 @@ class SVGPath(object):
+         self.transform = transform
+ 
+     @classmethod
+-    def fromstring(cls, data, transform=None):
++    def frombytes(cls, data, transform=None):
+         self = cls(transform=transform)
+-        self.root = ElementTree.fromstring(data)
++        self.root = ElementTree.frombytes(data)
+         return self
+ 
+     def draw(self, pen):
+diff --git a/Lib/fontTools/ttLib/tables/G_P_K_G_.py b/Lib/fontTools/ttLib/tables/G_P_K_G_.py
+index 4e13830..2849293 100644
+--- a/Lib/fontTools/ttLib/tables/G_P_K_G_.py
++++ b/Lib/fontTools/ttLib/tables/G_P_K_G_.py
+@@ -24,7 +24,7 @@ class table_G_P_K_G_(DefaultTable.DefaultTable):
+ 
+ 		GMAPoffsets = array.array("I")
+ 		endPos = (self.numGMAPs+1) * 4
+-		GMAPoffsets.fromstring(newData[:endPos])
++		GMAPoffsets.frombytes(newData[:endPos])
+ 		if sys.byteorder != "big":
+ 			GMAPoffsets.byteswap()
+ 		self.GMAPs = []
+@@ -35,7 +35,7 @@ class table_G_P_K_G_(DefaultTable.DefaultTable):
+ 		pos = endPos
+ 		endPos = pos + (self.numGlyplets + 1)*4
+ 		glyphletOffsets = array.array("I")
+-		glyphletOffsets.fromstring(newData[pos:endPos])
++		glyphletOffsets.frombytes(newData[pos:endPos])
+ 		if sys.byteorder != "big":
+ 			glyphletOffsets.byteswap()
+ 		self.glyphlets = []
+diff --git a/Lib/fontTools/ttLib/tables/G__l_o_c.py b/Lib/fontTools/ttLib/tables/G__l_o_c.py
+index d77c483..d1d62d1 100644
+--- a/Lib/fontTools/ttLib/tables/G__l_o_c.py
++++ b/Lib/fontTools/ttLib/tables/G__l_o_c.py
+@@ -29,11 +29,11 @@ class table_G__l_o_c(DefaultTable.DefaultTable):
+         flags = self.flags
+         del self.flags
+         self.locations = array.array('I' if flags & 1 else 'H')
+-        self.locations.fromstring(data[:len(data) - self.numAttribs * (flags & 2)])
++        self.locations.frombytes(data[:len(data) - self.numAttribs * (flags & 2)])
+         self.locations.byteswap()
+         self.attribIds = array.array('H')
+         if flags & 2:
+-            self.attribIds.fromstring(data[-self.numAttribs * 2:])
++            self.attribIds.frombytes(data[-self.numAttribs * 2:])
+             self.attribIds.byteswap()
+ 
+     def compile(self, ttFont):
+diff --git a/Lib/fontTools/ttLib/tables/L_T_S_H_.py b/Lib/fontTools/ttLib/tables/L_T_S_H_.py
+index dd0f195..6bb1df2 100644
+--- a/Lib/fontTools/ttLib/tables/L_T_S_H_.py
++++ b/Lib/fontTools/ttLib/tables/L_T_S_H_.py
+@@ -19,7 +19,7 @@ class table_L_T_S_H_(DefaultTable.DefaultTable):
+ 		# ouch: the assertion is not true in Chicago!
+ 		#assert numGlyphs == ttFont['maxp'].numGlyphs
+ 		yPels = array.array("B")
+-		yPels.fromstring(data)
++		yPels.frombytes(data)
+ 		self.yPels = {}
+ 		for i in range(numGlyphs):
+ 			self.yPels[ttFont.getGlyphName(i)] = yPels[i]
+diff --git a/Lib/fontTools/ttLib/tables/T_S_I__5.py b/Lib/fontTools/ttLib/tables/T_S_I__5.py
+index dbf9e5a..11a2018 100644
+--- a/Lib/fontTools/ttLib/tables/T_S_I__5.py
++++ b/Lib/fontTools/ttLib/tables/T_S_I__5.py
+@@ -17,7 +17,7 @@ class table_T_S_I__5(DefaultTable.DefaultTable):
+ 		numGlyphs = ttFont['maxp'].numGlyphs
+ 		assert len(data) == 2 * numGlyphs
+ 		a = array.array("H")
+-		a.fromstring(data)
++		a.frombytes(data)
+ 		if sys.byteorder != "big":
+ 			a.byteswap()
+ 		self.glyphGrouping = {}
+diff --git a/Lib/fontTools/ttLib/tables/TupleVariation.py b/Lib/fontTools/ttLib/tables/TupleVariation.py
+index 5fa71c8..e084dff 100644
+--- a/Lib/fontTools/ttLib/tables/TupleVariation.py
++++ b/Lib/fontTools/ttLib/tables/TupleVariation.py
+@@ -266,7 +266,7 @@ class TupleVariation(object):
+ 			else:
+ 				points = array.array("B")
+ 				pointsSize = numPointsInRun
+-			points.fromstring(data[pos:pos+pointsSize])
++			points.frombytes(data[pos:pos+pointsSize])
+ 			if sys.byteorder != "big":
+ 				points.byteswap()
+ 
+@@ -424,7 +424,7 @@ class TupleVariation(object):
+ 				else:
+ 					deltas = array.array("b")
+ 					deltasSize = numDeltasInRun
+-				deltas.fromstring(data[pos:pos+deltasSize])
++				deltas.frombytes(data[pos:pos+deltasSize])
+ 				if sys.byteorder != "big":
+ 					deltas.byteswap()
+ 				assert len(deltas) == numDeltasInRun
+diff --git a/Lib/fontTools/ttLib/tables/_c_m_a_p.py b/Lib/fontTools/ttLib/tables/_c_m_a_p.py
+index eccf69e..1eab2bf 100644
+--- a/Lib/fontTools/ttLib/tables/_c_m_a_p.py
++++ b/Lib/fontTools/ttLib/tables/_c_m_a_p.py
+@@ -254,7 +254,7 @@ class cmap_format_0(CmapSubtable):
+ 		data = self.data # decompileHeader assigns the data after the header to self.data
+ 		assert 262 == self.length, "Format 0 cmap subtable not 262 bytes"
+ 		gids = array.array("B")
+-		gids.fromstring(self.data)
++		gids.frombytes(self.data)
+ 		charCodes = list(range(len(gids)))
+ 		self.cmap = _make_map(self.ttFont, charCodes, gids)
+ 
+@@ -338,7 +338,7 @@ class cmap_format_2(CmapSubtable):
+ 		maxSubHeaderindex = 0
+ 		# get the key array, and determine the number of subHeaders.
+ 		allKeys = array.array("H")
+-		allKeys.fromstring(data[:512])
++		allKeys.frombytes(data[:512])
+ 		data = data[512:]
+ 		if sys.byteorder != "big":
+ 			allKeys.byteswap()
+@@ -355,7 +355,7 @@ class cmap_format_2(CmapSubtable):
+ 			pos += 8
+ 			giDataPos = pos + subHeader.idRangeOffset-2
+ 			giList = array.array("H")
+-			giList.fromstring(data[giDataPos:giDataPos + subHeader.entryCount*2])
++			giList.frombytes(data[giDataPos:giDataPos + subHeader.entryCount*2])
+ 			if sys.byteorder != "big":
+ 				giList.byteswap()
+ 			subHeader.glyphIndexArray = giList
+@@ -699,7 +699,7 @@ class cmap_format_4(CmapSubtable):
+ 		segCount = segCountX2 // 2
+ 
+ 		allCodes = array.array("H")
+-		allCodes.fromstring(data)
++		allCodes.frombytes(data)
+ 		self.data = data = None
+ 
+ 		if sys.byteorder != "big":
+@@ -871,7 +871,7 @@ class cmap_format_6(CmapSubtable):
+ 		data = data[4:]
+ 		#assert len(data) == 2 * entryCount  # XXX not true in Apple's Helvetica!!!
+ 		gids = array.array("H")
+-		gids.fromstring(data[:2 * int(entryCount)])
++		gids.frombytes(data[:2 * int(entryCount)])
+ 		if sys.byteorder != "big":
+ 			gids.byteswap()
+ 		self.data = data = None
+diff --git a/Lib/fontTools/ttLib/tables/_c_v_t.py b/Lib/fontTools/ttLib/tables/_c_v_t.py
+index 4fbee7b..5e42dd0 100644
+--- a/Lib/fontTools/ttLib/tables/_c_v_t.py
++++ b/Lib/fontTools/ttLib/tables/_c_v_t.py
+@@ -9,7 +9,7 @@ class table__c_v_t(DefaultTable.DefaultTable):
+ 
+ 	def decompile(self, data, ttFont):
+ 		values = array.array("h")
+-		values.fromstring(data)
++		values.frombytes(data)
+ 		if sys.byteorder != "big":
+ 			values.byteswap()
+ 		self.values = values
+diff --git a/Lib/fontTools/ttLib/tables/_g_l_y_f.py b/Lib/fontTools/ttLib/tables/_g_l_y_f.py
+index 58c1eb2..3598b15 100644
+--- a/Lib/fontTools/ttLib/tables/_g_l_y_f.py
++++ b/Lib/fontTools/ttLib/tables/_g_l_y_f.py
+@@ -511,7 +511,7 @@ class Glyph(object):
+ 
+ 	def decompileCoordinates(self, data):
+ 		endPtsOfContours = array.array("h")
+-		endPtsOfContours.fromstring(data[:2*self.numberOfContours])
++		endPtsOfContours.frombytes(data[:2*self.numberOfContours])
+ 		if sys.byteorder != "big":
+ 			endPtsOfContours.byteswap()
+ 		self.endPtsOfContours = endPtsOfContours.tolist()
+diff --git a/Lib/fontTools/ttLib/tables/_g_v_a_r.py b/Lib/fontTools/ttLib/tables/_g_v_a_r.py
+index 9f97c31..0d5f79a 100644
+--- a/Lib/fontTools/ttLib/tables/_g_v_a_r.py
++++ b/Lib/fontTools/ttLib/tables/_g_v_a_r.py
+@@ -120,7 +120,7 @@ class table__g_v_a_r(DefaultTable.DefaultTable):
+ 			# Long format: array of UInt32
+ 			offsets = array.array("I")
+ 			offsetsSize = (glyphCount + 1) * 4
+-		offsets.fromstring(data[0 : offsetsSize])
++		offsets.frombytes(data[0 : offsetsSize])
+ 		if sys.byteorder != "big":
+ 			offsets.byteswap()
+ 
+diff --git a/Lib/fontTools/ttLib/tables/_l_o_c_a.py b/Lib/fontTools/ttLib/tables/_l_o_c_a.py
+index 2fcd528..e4bafa1 100644
+--- a/Lib/fontTools/ttLib/tables/_l_o_c_a.py
++++ b/Lib/fontTools/ttLib/tables/_l_o_c_a.py
+@@ -20,7 +20,7 @@ class table__l_o_c_a(DefaultTable.DefaultTable):
+ 		else:
+ 			format = "H"
+ 		locations = array.array(format)
+-		locations.fromstring(data)
++		locations.frombytes(data)
+ 		if sys.byteorder != "big":
+ 			locations.byteswap()
+ 		if not longFormat:
+diff --git a/Lib/fontTools/ttLib/tables/_p_o_s_t.py b/Lib/fontTools/ttLib/tables/_p_o_s_t.py
+index ede62da..3399cad 100644
+--- a/Lib/fontTools/ttLib/tables/_p_o_s_t.py
++++ b/Lib/fontTools/ttLib/tables/_p_o_s_t.py
+@@ -83,7 +83,7 @@ class table__p_o_s_t(DefaultTable.DefaultTable):
+ 			numGlyphs = ttFont['maxp'].numGlyphs
+ 		data = data[2:]
+ 		indices = array.array("H")
+-		indices.fromstring(data[:2*numGlyphs])
++		indices.frombytes(data[:2*numGlyphs])
+ 		if sys.byteorder != "big":
+ 			indices.byteswap()
+ 		data = data[2*numGlyphs:]
+@@ -133,7 +133,7 @@ class table__p_o_s_t(DefaultTable.DefaultTable):
+ 		from fontTools import agl
+ 		numGlyphs = ttFont['maxp'].numGlyphs
+ 		indices = array.array("H")
+-		indices.fromstring(data)
++		indices.frombytes(data)
+ 		if sys.byteorder != "big":
+ 			indices.byteswap()
+ 		# In some older fonts, the size of the post table doesn't match
+diff --git a/Lib/fontTools/varLib/designspace.py b/Lib/fontTools/varLib/designspace.py
+index 7f235af..64fd7a4 100644
+--- a/Lib/fontTools/varLib/designspace.py
++++ b/Lib/fontTools/varLib/designspace.py
+@@ -104,7 +104,7 @@ def load(filename):
+ 
+ def loads(string):
+ 	"""Load designspace from a string."""
+-	return _load(ET.fromstring(string))
++	return _load(ET.frombytes(string))
+ 
+ if __name__ == '__main__':
+ 	import sys
+diff --git a/Snippets/svg2glif.py b/Snippets/svg2glif.py
+index 2dd6402..a6e4e58 100755
+--- a/Snippets/svg2glif.py
++++ b/Snippets/svg2glif.py
+@@ -24,7 +24,7 @@ def svg2glif(svg, name, width=0, height=0, unicodes=None, transform=None,
+     conversion (must be tuple of 6 floats, or a FontTools Transform object).
+     """
+     glyph = SimpleNamespace(width=width, height=height, unicodes=unicodes)
+-    outline = SVGPath.fromstring(svg, transform=transform)
++    outline = SVGPath.frombytes(svg, transform=transform)
+ 
+     # writeGlyphToString takes a callable (usually a glyph's drawPoints
+     # method) that accepts a PointPen, however SVGPath currently only has
+diff --git a/Tests/svgLib/path/path_test.py b/Tests/svgLib/path/path_test.py
+index 09b9447..4bdc844 100644
+--- a/Tests/svgLib/path/path_test.py
++++ b/Tests/svgLib/path/path_test.py
+@@ -50,16 +50,16 @@ class SVGPathTest(object):
+ 
+         assert pen.value == EXPECTED_PEN_COMMANDS
+ 
+-    def test_fromstring(self):
++    def test_frombytes(self):
+         pen = RecordingPen()
+-        svg = SVGPath.fromstring(SVG_DATA)
++        svg = SVGPath.frombytes(SVG_DATA)
+         svg.draw(pen)
+ 
+         assert pen.value == EXPECTED_PEN_COMMANDS
+ 
+     def test_transform(self):
+         pen = RecordingPen()
+-        svg = SVGPath.fromstring(SVG_DATA,
++        svg = SVGPath.frombytes(SVG_DATA,
+                                  transform=(1.0, 0, 0, -1.0, 0, 1000))
+         svg.draw(pen)
+ 
+-- 
+2.23.0
+
diff --git a/replace-totring-with-tobytes.patch b/replace-totring-with-tobytes.patch
new file mode 100644
index 0000000..0ffc8b0
--- /dev/null
+++ b/replace-totring-with-tobytes.patch
@@ -0,0 +1,342 @@
+From 791f619029931e9e80a8286f74cd14da3a142f98 Mon Sep 17 00:00:00 2001
+From: Chris Simpkins <git.simpkins@gmail.com>
+Date: Thu, 29 Aug 2019 23:21:22 -0400
+Subject: [PATCH] refactor array.tostring to array.tobytes
+
+the array.tostring method is deprecated
+---
+ Lib/fontTools/designspaceLib/__init__.py |  2 +-
+ Lib/fontTools/subset/__init__.py         |  2 +-
+ Lib/fontTools/ttLib/tables/G_P_K_G_.py   |  4 ++--
+ Lib/fontTools/ttLib/tables/G__l_o_c.py   |  4 ++--
+ Lib/fontTools/ttLib/tables/L_T_S_H_.py   |  2 +-
+ Lib/fontTools/ttLib/tables/S_V_G_.py     |  2 +-
+ Lib/fontTools/ttLib/tables/S__i_l_f.py   |  2 +-
+ Lib/fontTools/ttLib/tables/T_S_I__5.py   |  2 +-
+ Lib/fontTools/ttLib/tables/_c_m_a_p.py   |  6 +++---
+ Lib/fontTools/ttLib/tables/_c_v_t.py     |  2 +-
+ Lib/fontTools/ttLib/tables/_g_l_y_f.py   | 12 ++++++------
+ Lib/fontTools/ttLib/tables/_g_v_a_r.py   |  2 +-
+ Lib/fontTools/ttLib/tables/_h_m_t_x.py   |  2 +-
+ Lib/fontTools/ttLib/tables/_l_o_c_a.py   |  2 +-
+ Lib/fontTools/ttLib/tables/_p_o_s_t.py   |  4 ++--
+ Lib/fontTools/ttLib/tables/ttProgram.py  |  2 +-
+ Lib/fontTools/ttLib/woff2.py             |  8 ++++----
+ 17 files changed, 30 insertions(+), 30 deletions(-)
+
+diff --git a/Lib/fontTools/designspaceLib/__init__.py b/Lib/fontTools/designspaceLib/__init__.py
+index 72a4cee..3061691 100644
+--- a/Lib/fontTools/designspaceLib/__init__.py
++++ b/Lib/fontTools/designspaceLib/__init__.py
+@@ -46,7 +46,7 @@ def from_plist(element):
+         return {}
+     plist = ET.Element('plist')
+     plist.append(element)
+-    string = ET.tostring(plist)
++    string = ET.tobytes(plist)
+     try:
+         # Python 2
+         return plistlib.readPlistFromString(string)
+diff --git a/Lib/fontTools/subset/__init__.py b/Lib/fontTools/subset/__init__.py
+index 53d1dc3..21d43d5 100644
+--- a/Lib/fontTools/subset/__init__.py
++++ b/Lib/fontTools/subset/__init__.py
+@@ -2020,7 +2020,7 @@ def remapComponentsFast(self, indices):
+ 		elif flags & 0x0080: i += 8	# WE_HAVE_A_TWO_BY_TWO
+ 		more = flags & 0x0020	# MORE_COMPONENTS
+ 
+-	self.data = data.tostring()
++	self.data = data.tobyteswq()
+ 
+ @_add_method(ttLib.getTableClass('glyf'))
+ def closure_glyphs(self, s):
+diff --git a/Lib/fontTools/ttLib/tables/G_P_K_G_.py b/Lib/fontTools/ttLib/tables/G_P_K_G_.py
+index 2849293..02c429c 100644
+--- a/Lib/fontTools/ttLib/tables/G_P_K_G_.py
++++ b/Lib/fontTools/ttLib/tables/G_P_K_G_.py
+@@ -60,7 +60,7 @@ class table_G_P_K_G_(DefaultTable.DefaultTable):
+ 		gmapArray = array.array("I", GMAPoffsets)
+ 		if sys.byteorder != "big":
+ 			gmapArray.byteswap()
+-		dataList.append(gmapArray.tostring())
++		dataList.append(gmapArray.tobytes())
+ 
+ 		glyphletOffsets[0] = pos
+ 		for i in range(1, self.numGlyplets +1):
+@@ -69,7 +69,7 @@ class table_G_P_K_G_(DefaultTable.DefaultTable):
+ 		glyphletArray = array.array("I", glyphletOffsets)
+ 		if sys.byteorder != "big":
+ 			glyphletArray.byteswap()
+-		dataList.append(glyphletArray.tostring())
++		dataList.append(glyphletArray.tobytes())
+ 		dataList += self.GMAPs
+ 		dataList += self.glyphlets
+ 		data = bytesjoin(dataList)
+diff --git a/Lib/fontTools/ttLib/tables/G__l_o_c.py b/Lib/fontTools/ttLib/tables/G__l_o_c.py
+index d1d62d1..27ef623 100644
+--- a/Lib/fontTools/ttLib/tables/G__l_o_c.py
++++ b/Lib/fontTools/ttLib/tables/G__l_o_c.py
+@@ -41,11 +41,11 @@ class table_G__l_o_c(DefaultTable.DefaultTable):
+                 flags=(bool(self.attribIds) << 1) + (self.locations.typecode == 'I'),
+                 numAttribs=self.numAttribs))
+         self.locations.byteswap()
+-        data += self.locations.tostring()
++        data += self.locations.tobytes()
+         self.locations.byteswap()
+         if self.attribIds:
+             self.attribIds.byteswap()
+-            data += self.attribIds.tostring()
++            data += self.attribIds.tobytes()
+             self.attribIds.byteswap()
+         return data
+ 
+diff --git a/Lib/fontTools/ttLib/tables/L_T_S_H_.py b/Lib/fontTools/ttLib/tables/L_T_S_H_.py
+index 6bb1df2..b7d23bf 100644
+--- a/Lib/fontTools/ttLib/tables/L_T_S_H_.py
++++ b/Lib/fontTools/ttLib/tables/L_T_S_H_.py
+@@ -34,7 +34,7 @@ class table_L_T_S_H_(DefaultTable.DefaultTable):
+ 		for name in names:
+ 			yPels[ttFont.getGlyphID(name)] = self.yPels[name]
+ 		yPels = array.array("B", yPels)
+-		return struct.pack(">HH", version, numGlyphs) + yPels.tostring()
++		return struct.pack(">HH", version, numGlyphs) + yPels.tobytes()
+ 
+ 	def toXML(self, writer, ttFont):
+ 		names = sorted(self.yPels.keys())
+diff --git a/Lib/fontTools/ttLib/tables/S_V_G_.py b/Lib/fontTools/ttLib/tables/S_V_G_.py
+index b061153..a27153f 100644
+--- a/Lib/fontTools/ttLib/tables/S_V_G_.py
++++ b/Lib/fontTools/ttLib/tables/S_V_G_.py
+@@ -60,7 +60,7 @@ the number of <colorParamUINameID> elements.
+ 
+ XML = ET.XML
+ XMLElement = ET.Element
+-xmlToString = ET.tostring
++xmlToString = ET.tobytes
+ 
+ SVG_format_0 = """
+ 	>   # big endian
+diff --git a/Lib/fontTools/ttLib/tables/S__i_l_f.py b/Lib/fontTools/ttLib/tables/S__i_l_f.py
+index 2afd71e..067cd15 100644
+--- a/Lib/fontTools/ttLib/tables/S__i_l_f.py
++++ b/Lib/fontTools/ttLib/tables/S__i_l_f.py
+@@ -739,7 +739,7 @@ class Pass(object):
+         transes = []
+         for t in self.stateTrans:
+             t.byteswap()
+-            transes.append(t.tostring())
++            transes.append(t.tobytes())
+             t.byteswap()
+         if not len(transes):
+             self.startStates = [0]
+diff --git a/Lib/fontTools/ttLib/tables/T_S_I__5.py b/Lib/fontTools/ttLib/tables/T_S_I__5.py
+index 11a2018..7b19607 100644
+--- a/Lib/fontTools/ttLib/tables/T_S_I__5.py
++++ b/Lib/fontTools/ttLib/tables/T_S_I__5.py
+@@ -31,7 +31,7 @@ class table_T_S_I__5(DefaultTable.DefaultTable):
+ 			a.append(self.glyphGrouping.get(glyphNames[i], 0))
+ 		if sys.byteorder != "big":
+ 			a.byteswap()
+-		return a.tostring()
++		return a.tobytes()
+ 
+ 	def toXML(self, writer, ttFont):
+ 		names = sorted(self.glyphGrouping.keys())
+diff --git a/Lib/fontTools/ttLib/tables/_c_m_a_p.py b/Lib/fontTools/ttLib/tables/_c_m_a_p.py
+index 1eab2bf..cd14565 100644
+--- a/Lib/fontTools/ttLib/tables/_c_m_a_p.py
++++ b/Lib/fontTools/ttLib/tables/_c_m_a_p.py
+@@ -268,7 +268,7 @@ class cmap_format_0(CmapSubtable):
+ 		valueList = [getGlyphID(cmap[i]) if i in cmap else 0 for i in range(256)]
+ 
+ 		gids = array.array("B", valueList)
+-		data = struct.pack(">HHH", 0, 262, self.language) + gids.tostring()
++		data = struct.pack(">HHH", 0, 262, self.language) + gids.tobytes()
+ 		assert len(data) == 262
+ 		return data
+ 
+@@ -833,7 +833,7 @@ class cmap_format_4(CmapSubtable):
+ 			charCodeArray.byteswap()
+ 			idDeltaArray.byteswap()
+ 			restArray.byteswap()
+-		data = charCodeArray.tostring() + idDeltaArray.tostring() + restArray.tostring()
++		data = charCodeArray.tobytes() + idDeltaArray.tobytes() + restArray.tobytes()
+ 
+ 		length = struct.calcsize(cmap_format_4_format) + len(data)
+ 		header = struct.pack(cmap_format_4_format, self.format, length, self.language,
+@@ -894,7 +894,7 @@ class cmap_format_6(CmapSubtable):
+ 			gids = array.array("H", valueList)
+ 			if sys.byteorder != "big":
+ 				gids.byteswap()
+-			data = gids.tostring()
++			data = gids.tobytes()
+ 		else:
+ 			data = b""
+ 			firstCode = 0
+diff --git a/Lib/fontTools/ttLib/tables/_c_v_t.py b/Lib/fontTools/ttLib/tables/_c_v_t.py
+index 5e42dd0..9c1563a 100644
+--- a/Lib/fontTools/ttLib/tables/_c_v_t.py
++++ b/Lib/fontTools/ttLib/tables/_c_v_t.py
+@@ -18,7 +18,7 @@ class table__c_v_t(DefaultTable.DefaultTable):
+ 		values = self.values[:]
+ 		if sys.byteorder != "big":
+ 			values.byteswap()
+-		return values.tostring()
++		return values.tobytes()
+ 
+ 	def toXML(self, writer, ttFont):
+ 		for i in range(len(self.values)):
+diff --git a/Lib/fontTools/ttLib/tables/_g_l_y_f.py b/Lib/fontTools/ttLib/tables/_g_l_y_f.py
+index 3598b15..f189eee 100644
+--- a/Lib/fontTools/ttLib/tables/_g_l_y_f.py
++++ b/Lib/fontTools/ttLib/tables/_g_l_y_f.py
+@@ -627,7 +627,7 @@ class Glyph(object):
+ 		endPtsOfContours = array.array("h", self.endPtsOfContours)
+ 		if sys.byteorder != "big":
+ 			endPtsOfContours.byteswap()
+-		data.append(endPtsOfContours.tostring())
++		data.append(endPtsOfContours.tobytes())
+ 		instructions = self.program.getBytecode()
+ 		data.append(struct.pack(">h", len(instructions)))
+ 		data.append(instructions)
+@@ -691,7 +691,7 @@ class Glyph(object):
+ 				repeat = 0
+ 				compressedflags.append(flag)
+ 			lastflag = flag
+-		compressedFlags = array.array("B", compressedflags).tostring()
++		compressedFlags = array.array("B", compressedflags).tobytes()
+ 		compressedXs = bytesjoin(xPoints)
+ 		compressedYs = bytesjoin(yPoints)
+ 		return (compressedFlags, compressedXs, compressedYs)
+@@ -746,9 +746,9 @@ class Glyph(object):
+ 			raise Exception("internal error")
+ 		except StopIteration:
+ 			pass
+-		compressedFlags = compressedFlags.tostring()
+-		compressedXs = compressedXs.tostring()
+-		compressedYs = compressedYs.tostring()
++		compressedFlags = compressedFlags.tobytes()
++		compressedXs = compressedXs.tobytes()
++		compressedYs = compressedYs.tobytes()
+ 
+ 		return (compressedFlags, compressedXs, compressedYs)
+ 
+@@ -981,7 +981,7 @@ class Glyph(object):
+ 			# Remove padding
+ 			data = data[:i]
+ 
+-		self.data = data.tostring()
++		self.data = data.tobytes()
+ 
+ 	def removeHinting(self):
+ 		self.trim (remove_hinting=True)
+diff --git a/Lib/fontTools/ttLib/tables/_g_v_a_r.py b/Lib/fontTools/ttLib/tables/_g_v_a_r.py
+index 0d5f79a..02ddf20 100644
+--- a/Lib/fontTools/ttLib/tables/_g_v_a_r.py
++++ b/Lib/fontTools/ttLib/tables/_g_v_a_r.py
+@@ -154,7 +154,7 @@ class table__g_v_a_r(DefaultTable.DefaultTable):
+ 			tableFormat = 1
+ 		if sys.byteorder != "big":
+ 			packed.byteswap()
+-		return (packed.tostring(), tableFormat)
++		return (packed.tobytes(), tableFormat)
+ 
+ 	def toXML(self, writer, ttFont):
+ 		writer.simpletag("version", value=self.version)
+diff --git a/Lib/fontTools/ttLib/tables/_h_m_t_x.py b/Lib/fontTools/ttLib/tables/_h_m_t_x.py
+index e6b8ea9..5a02150 100644
+--- a/Lib/fontTools/ttLib/tables/_h_m_t_x.py
++++ b/Lib/fontTools/ttLib/tables/_h_m_t_x.py
+@@ -100,7 +100,7 @@ class table__h_m_t_x(DefaultTable.DefaultTable):
+ 		additionalMetrics = array.array("h", additionalMetrics)
+ 		if sys.byteorder != "big":
+ 			additionalMetrics.byteswap()
+-		data = data + additionalMetrics.tostring()
++		data = data + additionalMetrics.tobytes()
+ 		return data
+ 
+ 	def toXML(self, writer, ttFont):
+diff --git a/Lib/fontTools/ttLib/tables/_l_o_c_a.py b/Lib/fontTools/ttLib/tables/_l_o_c_a.py
+index e4bafa1..da8cbb5 100644
+--- a/Lib/fontTools/ttLib/tables/_l_o_c_a.py
++++ b/Lib/fontTools/ttLib/tables/_l_o_c_a.py
+@@ -49,7 +49,7 @@ class table__l_o_c_a(DefaultTable.DefaultTable):
+ 			ttFont['head'].indexToLocFormat = 1
+ 		if sys.byteorder != "big":
+ 			locations.byteswap()
+-		return locations.tostring()
++		return locations.tobytes()
+ 
+ 	def set(self, locations):
+ 		self.locations = array.array("I", locations)
+diff --git a/Lib/fontTools/ttLib/tables/_p_o_s_t.py b/Lib/fontTools/ttLib/tables/_p_o_s_t.py
+index 3399cad..98eaac7 100644
+--- a/Lib/fontTools/ttLib/tables/_p_o_s_t.py
++++ b/Lib/fontTools/ttLib/tables/_p_o_s_t.py
+@@ -175,7 +175,7 @@ class table__p_o_s_t(DefaultTable.DefaultTable):
+ 			indices.append(index)
+ 		if sys.byteorder != "big":
+ 			indices.byteswap()
+-		return struct.pack(">H", numGlyphs) + indices.tostring() + packPStrings(extraNames)
++		return struct.pack(">H", numGlyphs) + indices.tobytes() + packPStrings(extraNames)
+ 
+ 	def encode_format_4_0(self, ttFont):
+ 		from fontTools import agl
+@@ -193,7 +193,7 @@ class table__p_o_s_t(DefaultTable.DefaultTable):
+ 				indices.append(0xFFFF)
+ 		if sys.byteorder != "big":
+ 			indices.byteswap()
+-		return indices.tostring()
++		return indices.tobytes()
+ 
+ 	def toXML(self, writer, ttFont):
+ 		formatstring, names, fixes = sstruct.getformat(postFormat)
+diff --git a/Lib/fontTools/ttLib/tables/ttProgram.py b/Lib/fontTools/ttLib/tables/ttProgram.py
+index 182982f..e13e942 100644
+--- a/Lib/fontTools/ttLib/tables/ttProgram.py
++++ b/Lib/fontTools/ttLib/tables/ttProgram.py
+@@ -222,7 +222,7 @@ class Program(object):
+ 	def getBytecode(self):
+ 		if not hasattr(self, "bytecode"):
+ 			self._assemble()
+-		return self.bytecode.tostring()
++		return self.bytecode.tobytes()
+ 
+ 	def getAssembly(self, preserve=True):
+ 		if not hasattr(self, "assembly"):
+diff --git a/Lib/fontTools/ttLib/woff2.py b/Lib/fontTools/ttLib/woff2.py
+index 1952682..d73009b 100644
+--- a/Lib/fontTools/ttLib/woff2.py
++++ b/Lib/fontTools/ttLib/woff2.py
+@@ -584,7 +584,7 @@ class WOFF2LocaTable(getTableClass('loca')):
+ 				locations = array.array("I", self.locations)
+ 			if sys.byteorder != "big":
+ 				locations.byteswap()
+-			data = locations.tostring()
++			data = locations.tobytes()
+ 		else:
+ 			# use the most compact indexFormat given the current glyph offsets
+ 			data = super(WOFF2LocaTable, self).compile(ttFont)
+@@ -679,7 +679,7 @@ class WOFF2GlyfTable(getTableClass('glyf')):
+ 		for glyphID in range(self.numGlyphs):
+ 			self._encodeGlyph(glyphID)
+ 
+-		self.bboxStream = self.bboxBitmap.tostring() + self.bboxStream
++		self.bboxStream = self.bboxBitmap.tobytes() + self.bboxStream
+ 		for stream in self.subStreams:
+ 			setattr(self, stream + 'Size', len(getattr(self, stream)))
+ 		self.version = 0
+@@ -907,8 +907,8 @@ class WOFF2GlyfTable(getTableClass('glyf')):
+ 				triplets.append(absY >> 8)
+ 				triplets.append(absY & 0xff)
+ 
+-		self.flagStream += flags.tostring()
+-		self.glyphStream += triplets.tostring()
++		self.flagStream += flags.tobytes()
++		self.glyphStream += triplets.tobytes()
+ 
+ 
+ class WOFF2FlavorData(WOFFFlavorData):
+-- 
+2.23.0
+