Incorrect text node escaping

[vit9696]

Running the following code sample with:

• Python 3.11.6
• graphviz 9.0.0 (20230911.1827)
• pygraphviz 1.12

import sys
import pygraphviz

G = pygraphviz.AGraph(strict=False, directed=True, name="TEST", fontsize=11.0)

label = 'Test Test test test test test testtest test\l"test test test test test test test test'

n = G.add_node("TESTTEST", label=label, tooltip="", shape="rectangle", style="solid")
G.layout(prog='dot')
G.draw(sys.stdout.buffer, format='svg')

Produces the following error:

Traceback (most recent call last):
  File "/t.py", line 10, in <module>
    G.layout(prog='dot')
  File "/usr/local/lib/python3.11/site-packages/pygraphviz/agraph.py", line 1483, in layout
    data = self._run_prog(prog, " ".join([args, "-T", output_fmt]))
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/pygraphviz/agraph.py", line 1404, in _run_prog
    raise OSError(b"".join(errors).decode(self.encoding))
OSError: Error: <stdin>: syntax error in line 4 near 'test'

Debugging shows that the issue is apparently caused by unescaped quote during the layout process:

digraph TEST {
	graph [fontsize=11.0];
	node [label="\N"];
	TESTTEST	[label="Test Test test test test test testtest test\l"test test test test test test test test",
		shape=rectangle,
		style=solid];
}

Reproduced on macOS and Arch Linux.