hdlparse dependency preventing readthedocs generation

[mithro]

https://readthedocs.org/projects/sky130-fd-pr-reram/builds/15345432/

Requirement already satisfied: sphinxcontrib-serializinghtml>=1.1.5 in /home/docs/checkouts/readthedocs.org/user_builds/sky130-fd-pr-reram/envs/stable/lib/python3.7/site-packages (from sphinx->-r docs/requirements.txt (line 3)) (1.1.5)
Requirement already satisfied: alabaster<0.8,>=0.7 in /home/docs/checkouts/readthedocs.org/user_builds/sky130-fd-pr-reram/envs/stable/lib/python3.7/site-packages (from sphinx->-r docs/requirements.txt (line 3)) (0.7.12)
Requirement already satisfied: sphinxcontrib-applehelp in /home/docs/checkouts/readthedocs.org/user_builds/sky130-fd-pr-reram/envs/stable/lib/python3.7/site-packages (from sphinx->-r docs/requirements.txt (line 3)) (1.0.2)
Requirement already satisfied: packaging in /home/docs/checkouts/readthedocs.org/user_builds/sky130-fd-pr-reram/envs/stable/lib/python3.7/site-packages (from sphinx->-r docs/requirements.txt (line 3)) (21.3)
Requirement already satisfied: sphinxcontrib-jsmath in /home/docs/checkouts/readthedocs.org/user_builds/sky130-fd-pr-reram/envs/stable/lib/python3.7/site-packages (from sphinx->-r docs/requirements.txt (line 3)) (1.0.1)
Requirement already satisfied: sphinxcontrib-htmlhelp>=2.0.0 in /home/docs/checkouts/readthedocs.org/user_builds/sky130-fd-pr-reram/envs/stable/lib/python3.7/site-packages (from sphinx->-r docs/requirements.txt (line 3)) (2.0.0)
Collecting livereload
  Downloading livereload-2.6.3.tar.gz (25 kB)
  Preparing metadata (setup.py): started
  Preparing metadata (setup.py): finished with status 'done'
Collecting colorama
  Downloading colorama-0.4.4-py2.py3-none-any.whl (16 kB)
Collecting lark-parser
  Downloading lark_parser-0.12.0-py2.py3-none-any.whl (103 kB)
Collecting yowasp-yosys
  Downloading yowasp_yosys-0.11.post47.dev261-py3-none-any.whl (6.8 MB)
Collecting nmigen
  Downloading nmigen-0.2.tar.gz (144 kB)
  Preparing metadata (setup.py): started
  Preparing metadata (setup.py): finished with status 'done'
Collecting hdlparse>=1.0.4
  Downloading hdlparse-1.0.4.tar.gz (10 kB)
  Preparing metadata (setup.py): started
  Preparing metadata (setup.py): finished with status 'error'
  ERROR: Command errored out with exit status 1:
   command: /home/docs/checkouts/readthedocs.org/user_builds/sky130-fd-pr-reram/envs/stable/bin/python -c 'import io, os, sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-gutg_mhl/hdlparse_7acbb01ea8a24a8f9394b84071985e5a/setup.py'"'"'; __file__='"'"'/tmp/pip-install-gutg_mhl/hdlparse_7acbb01ea8a24a8f9394b84071985e5a/setup.py'"'"';f = getattr(tokenize, '"'"'open'"'"', open)(__file__) if os.path.exists(__file__) else io.StringIO('"'"'from setuptools import setup; setup()'"'"');code = f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' egg_info --egg-base /tmp/pip-pip-egg-info-21qf9112
       cwd: /tmp/pip-install-gutg_mhl/hdlparse_7acbb01ea8a24a8f9394b84071985e5a/
  Complete output (1 lines):
  error in hdlparse setup command: use_2to3 is invalid.
  ----------------------------------------
WARNING: Discarding https://files.pythonhosted.org/packages/6c/61/4b0f9c9bf7562ebf98617c5c300843776f38e4588491985a40e464f3d14e/hdlparse-1.0.4.tar.gz#sha256=fb6230ed1e7a04a8f82f8d3fb59791d0751ae35e5b8e58dbbf2cbcf100d0d0f2 (from https://pypi.org/simple/hdlparse/). Command errored out with exit status 1: python setup.py egg_info Check the logs for full command output.
INFO: pip is looking at multiple versions of sphinxcontrib-hdl-diagrams to determine which version is compatible with other requirements. This could take a while.
Collecting sphinxcontrib-hdl-diagrams
  Downloading sphinxcontrib_hdl_diagrams-0.0.post131-py3-none-any.whl (13 kB)
INFO: pip is looking at multiple versions of sphinx-verilog-domain to determine which version is compatible with other requirements. This could take a while.
Collecting sphinx-verilog-domain
  Downloading sphinx_verilog_domain-0.0.2-py3-none-any.whl (12 kB)
INFO: pip is looking at multiple versions of <Python from Requires-Python> to determine which version is compatible with other requirements. This could take a while.
INFO: pip is looking at multiple versions of sphinx-autobuild to determine which version is compatible with other requirements. This could take a while.
Collecting sphinx-autobuild
  Downloading sphinx_autobuild-2020.9.1-py3-none-any.whl (9.8 kB)
INFO: pip is looking at multiple versions of sphinx to determine which version is compatible with other requirements. This could take a while.
Collecting sphinx
  Downloading Sphinx-4.3.0-py3-none-any.whl (3.1 MB)
INFO: pip is looking at multiple versions of docutils to determine which version is compatible with other requirements. This could take a while.
Collecting docutils
  Downloading docutils-0.18-py2.py3-none-any.whl (569 kB)
INFO: pip is looking at multiple versions of sphinx-symbiflow-theme to determine which version is compatible with other requirements. This could take a while.
ERROR: Could not find a version that satisfies the requirement hdlparse>=1.0.4 (from symbolator) (from versions: 1.0.1, 1.0.3, 1.0.4)
ERROR: No matching distribution found for hdlparse>=1.0.4