Command /home/docs/checkouts/readthedocs.org/user_builds/hypertools/envs/stable/bin/python -m pip install --exists-action=w --no-cache-dir -r docs/doc_requirements.txt failed: Collecting sphinx==2.3.0 Downloading Sphinx-2.3.0-py3-none-any.whl (2.7 MB) Collecting sphinx_bootstrap_theme==0.6.4 Downloading sphinx-bootstrap-theme-0.6.4.tar.gz (1.2 MB) 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/hypertools/envs/stable/bin/python -c 'import io, os, sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-7_j335_u/sphinx-bootstrap-theme_cc5ecc98d82e45238bdd161987de180a/setup.py'"'"'; __file__='"'"'/tmp/pip-install-7_j335_u/sphinx-bootstrap-theme_cc5ecc98d82e45238bdd161987de180a/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-64teannl cwd: /tmp/pip-install-7_j335_u/sphinx-bootstrap-theme_cc5ecc98d82e45238bdd161987de180a/ Complete output (1 lines): error in sphinx-bootstrap-theme setup command: use_2to3 is invalid. ---------------------------------------- WARNING: Discarding https://files.pythonhosted.org/packages/be/b7/7af1125c5f8b2580b0ad8a0f5392b14866cc2e4bdd1113472b66e2249bde/sphinx-bootstrap-theme-0.6.4.tar.gz#sha256=edbae42653f1aeeece1b052bd5fa5ff59c1cdb85377de83f1281d487393f7e94 (from https://pypi.org/simple/sphinx-bootstrap-theme/). Command errored out with exit status 1: python setup.py egg_info Check the logs for full command output. ERROR: Could not find a version that satisfies the requirement sphinx_bootstrap_theme==0.6.4 (from versions: 0.1.0, 0.1.1, 0.1.2, 0.1.3, 0.1.4, 0.1.5, 0.1.6, 0.1.7, 0.1.8, 0.2.0, 0.2.1, 0.2.2, 0.2.3, 0.2.4, 0.2.5, 0.2.6, 0.2.7, 0.2.8, 0.2.9, 0.3.0, 0.3.1, 0.3.2, 0.3.3, 0.3.4, 0.3.5, 0.3.6, 0.3.7, 0.3.8, 0.3.9, 0.4.0, 0.4.1, 0.4.2, 0.4.3, 0.4.4, 0.4.5, 0.4.6, 0.4.7, 0.4.8, 0.4.9, 0.4.10, 0.4.11, 0.4.12, 0.4.13, 0.4.14, 0.5.0, 0.5.1, 0.5.2, 0.5.3, 0.6.0, 0.6.1, 0.6.2, 0.6.3, 0.6.4, 0.6.5, 0.7.0, 0.7.1, 0.8.0, 0.8.1) ERROR: No matching distribution found for sphinx_bootstrap_theme==0.6.4 WARNING: You are using pip version 21.3.1; however, version 22.0.3 is available. You should consider upgrading via the '/home/docs/checkouts/readthedocs.org/user_builds/hypertools/envs/stable/bin/python -m pip install --upgrade pip' command.