pygraphviz can not be installed

$ sudo pip3 install pygraphviz
WARNING: The directory '/home/usr1/.cache/pip' or its parent directory is not owned or is not writable by the current user. The cache has been disabled. Check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.
Looking in indexes: https://pypi.tuna.tsinghua.edu.cn/simple
Collecting pygraphviz
Downloading https://pypi.tuna.tsinghua.edu.cn/packages/7e/b1/d6d849ddaf6f11036f9980d433f383d4c13d1ebcfc3cd09bc845bda7e433/pygraphviz-1.5.zip (117 kB)
|████████████████████████████████| 117 kB 11.0 MB/s
Installing collected packages: pygraphviz
Running setup.py install for pygraphviz ... error
ERROR: Command errored out with exit status 1:
command: /usr/local/bin/python3.8 -u -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-0z76ssje/pygraphviz/setup.py'"'"'; __file__='"'"'/tmp/pip-install-0z76ssje/pygraphviz/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /tmp/pip-record-_abu592r/install-record.txt --single-version-externally-managed --compile --install-headers /usr/local/include/python3.8/pygraphviz
cwd: /tmp/pip-install-0z76ssje/pygraphviz/
Complete output (34 lines):
running install
Trying dpkg
dpkg-query: no path found matching pattern *graphviz*
Could not run dpkg
Trying pkg-config
Package libcgraph was not found in the pkg-config search path.
Perhaps you should add the directory containing `libcgraph.pc'
to the PKG_CONFIG_PATH environment variable
No package 'libcgraph' found
Traceback (most recent call last):
File "", line 1, in
File "/tmp/pip-install-0z76ssje/pygraphviz/setup.py", line 70, in
setup(
File "/usr/local/lib/python3.8/site-packages/setuptools/__init__.py", line 145, in setup
return distutils.core.setup(**attrs)
File "/usr/local/lib/python3.8/distutils/core.py", line 148, in setup
dist.run_commands()
File "/usr/local/lib/python3.8/distutils/dist.py", line 966, in run_commands
self.run_command(cmd)
File "/usr/local/lib/python3.8/distutils/dist.py", line 985, in run_command
cmd_obj.run()
File "/tmp/pip-install-0z76ssje/pygraphviz/setup_commands.py", line 44, in modified_run
self.include_path, self.library_path = get_graphviz_dirs()
File "/tmp/pip-install-0z76ssje/pygraphviz/setup_extra.py", line 162, in get_graphviz_dirs
include_dirs, library_dirs = _try_configure(include_dirs, library_dirs, _pkg_config)
File "/tmp/pip-install-0z76ssje/pygraphviz/setup_extra.py", line 117, in _try_configure
i, l = try_function()
File "/tmp/pip-install-0z76ssje/pygraphviz/setup_extra.py", line 72, in _pkg_config
output = S.check_output(['pkg-config', '--libs-only-L', 'libcgraph'])
File "/usr/local/lib/python3.8/subprocess.py", line 411, in check_output
return run(*popenargs, stdout=PIPE, timeout=timeout, check=True,
File "/usr/local/lib/python3.8/subprocess.py", line 512, in run
raise CalledProcessError(retcode, process.args,
subprocess.CalledProcessError: Command '['pkg-config', '--libs-only-L', 'libcgraph']' returned non-zero exit status 1.
----------------------------------------
ERROR: Command errored out with exit status 1: /usr/local/bin/python3.8 -u -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-0z76ssje/pygraphviz/setup.py'"'"'; __file__='"'"'/tmp/pip-install-0z76ssje/pygraphviz/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /tmp/pip-record-_abu592r/install-record.txt --single-version-externally-managed --compile --install-headers /usr/local/include/python3.8/pygraphviz Check the logs for full command output.

Start by reproducing the reported `pip3 install pygraphviz` failure and inspect the installation or dependency guidance for ENAS-pytorch. The log points to missing Graphviz `libcgraph` discovery through `pkg-config`; done means identifying a project-specific installation fix or documenting the required dependency and verifying installation succeeds.

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