Error log from sphinx-build with cryptic autodoc error.

log.txt

[autodoc] => <function counts_to_point at 0x7efe080810d0>
[app] emitting event: 'autodoc-before-process-signature'(<function counts_to_point at 0x7efe080810d0>, False)
[app] emitting event: 'autodoc-process-signature'('function', 'fractopo.analysis.parameters.counts_to_point', <function counts_to_point at 0x7efe0808
[app] emitting event: 'autodoc-process-docstring'('function', 'fractopo.analysis.parameters.counts_to_point', <function counts_to_point at 0x7efe0808

...

WARNING: multiple files found for the document "auto_examples/plot_validation_errors": ['auto_examples/plot_validation_errors.py.md5', 'auto_examples/plot_validation_errors.py', 'auto_examples/plot_validation_errors.ipynb', 'auto_examples/plot_validation_errors.rst']

...

Use '/home/nialov/projects/fractopo-build-python-3.11-support/docs_src/auto_examples/plot_validation_errors.rst' for the build.
[app] emitting event: 'build-finished'(ExtensionError("Handler <function process_docstring at 0x7efe073368b0> for event 'autodoc-process-d

Traceback (most recent call last):
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/sphinx/events.py", line 94, in emit
    results.append(listener.handler(self.app, *args))
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/sphinx_autodoc_typehints/__init__.py", line 539, in process_docstring
    _inject_types_to_docstring(type_hints, signature, original_obj, app, what, name, lines)
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/sphinx_autodoc_typehints/__init__.py", line 601, in _inject_types_to_docstring
    _inject_rtype(type_hints, original_obj, app, what, name, lines)
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/sphinx_autodoc_typehints/__init__.py", line 747, in _inject_rtype
    r = get_insert_index(app, lines)
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/sphinx_autodoc_typehints/__init__.py", line 725, in get_insert_index
    at = line_before_node(doc.children[idx])
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/sphinx_autodoc_typehints/__init__.py", line 664, in line_before_node
    assert line
AssertionError

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/sphinx/cmd/build.py", line 281, in build_main
    app.build(args.force_all, args.filenames)
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/sphinx/application.py", line 347, in build
    self.builder.build_update()
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/sphinx/builders/__init__.py", line 310, in build_update
    self.build(to_build,
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/sphinx/builders/__init__.py", line 326, in build
    updated_docnames = set(self.read())
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/sphinx/builders/__init__.py", line 433, in read
    self._read_serial(docnames)
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/sphinx/builders/__init__.py", line 454, in _read_serial
    self.read_doc(docname)
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/sphinx/builders/__init__.py", line 510, in read_doc
    publisher.publish()
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/docutils/core.py", line 217, in publish
    self.document = self.reader.read(self.source, self.parser,
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/sphinx/io.py", line 104, in read
    self.parse()
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/docutils/readers/__init__.py", line 78, in parse
    self.parser.parse(self.input, document)
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/sphinx/parsers.py", line 78, in parse
    self.statemachine.run(inputlines, document, inliner=self.inliner)
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/docutils/parsers/rst/states.py", line 170, in run
    results = StateMachineWS.run(self, input_lines, input_offset,
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/docutils/statemachine.py", line 239, in run
    context, next_state, result = self.check_line(
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/docutils/statemachine.py", line 451, in check_line
    return method(match, context, next_state)
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/docutils/parsers/rst/states.py", line 2769, in underline
    self.section(title, source, style, lineno - 1, messages)
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/docutils/parsers/rst/states.py", line 327, in section
    self.new_subsection(title, lineno, messages)
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/docutils/parsers/rst/states.py", line 393, in new_subsection
    newabsoffset = self.nested_parse(
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/docutils/parsers/rst/states.py", line 281, in nested_parse
    state_machine.run(block, input_offset, memo=self.memo,
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/docutils/parsers/rst/states.py", line 196, in run
    results = StateMachineWS.run(self, input_lines, input_offset)
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/docutils/statemachine.py", line 239, in run
    context, next_state, result = self.check_line(
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/docutils/statemachine.py", line 451, in check_line
    return method(match, context, next_state)
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/docutils/parsers/rst/states.py", line 2342, in explicit_markup
    nodelist, blank_finish = self.explicit_construct(match)
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/docutils/parsers/rst/states.py", line 2354, in explicit_construct
    return method(self, expmatch)
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/docutils/parsers/rst/states.py", line 2096, in directive
    return self.run_directive(
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/docutils/parsers/rst/states.py", line 2146, in run_directive
    result = directive_instance.run()
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/sphinx/ext/autodoc/directive.py", line 148, in run
    documenter.generate(more_content=self.content)
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/sphinx/ext/autodoc/__init__.py", line 954, in generate
    self.document_members(all_members)
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/sphinx/ext/autodoc/__init__.py", line 830, in document_members
    documenter.generate(
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/sphinx/ext/autodoc/__init__.py", line 951, in generate
    self.add_content(more_content)
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/sphinx/ext/autodoc/__init__.py", line 602, in add_content
    for i, line in enumerate(self.process_doc(docstrings)):
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/sphinx/ext/autodoc/__init__.py", line 547, in process_doc
    self.env.app.emit('autodoc-process-docstring',
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/sphinx/application.py", line 458, in emit
    return self.events.emit(event, *args, allowed_exceptions=allowed_exceptions)
  File "/home/nialov/projects/fractopo-build-python-3.11-support/.nox/docs/lib/python3.8/site-packages/sphinx/events.py", line 105, in emit
    raise ExtensionError(__("Handler %r for event %r threw an exception") %
sphinx.errors.ExtensionError: Handler <function process_docstring at 0x7efe073368b0> for event 'autodoc-process-docstring' threw an exception (exception: )

Extension error (sphinx_autodoc_typehints):
Handler <function process_docstring at 0x7efe073368b0> for event 'autodoc-process-docstring' threw an exception (exception: )
nox > Command sphinx-build docs_src docs -vvv failed with exit code 2
nox > Session docs failed.