Configuration error:
There is a programmable error in your configuration file:

Traceback (most recent call last):
  File "/home/circleci/project/venv/lib/python3.7/site-packages/nbformat/reader.py", line 14, in parse_json
    nb_dict = json.loads(s, **kwargs)
  File "/usr/local/lib/python3.7/json/__init__.py", line 348, in loads
    return _default_decoder.decode(s)
  File "/usr/local/lib/python3.7/json/decoder.py", line 337, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "/usr/local/lib/python3.7/json/decoder.py", line 353, in raw_decode
    obj, end = self.scan_once(s, idx)
json.decoder.JSONDecodeError: Expecting property name enclosed in double quotes: line 6 column 3 (char 67)

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

Traceback (most recent call last):
  File "/home/circleci/project/venv/lib/python3.7/site-packages/sphinx/config.py", line 348, in eval_config_file
    execfile_(filename, namespace)
  File "/home/circleci/project/venv/lib/python3.7/site-packages/sphinx/util/pycompat.py", line 81, in execfile_
    exec(code, _globals)
  File "/home/circleci/project/tutorials/conf.py", line 164, in <module>
    process_notebooks(nb_tutorials_path, **processkwargs)
  File "/home/circleci/project/scripts/convert.py", line 238, in process_notebooks
    nbc.execute()
  File "/home/circleci/project/scripts/convert.py", line 94, in execute
    nb = nbformat.read(f, as_version=IPYTHON_VERSION)
  File "/home/circleci/project/venv/lib/python3.7/site-packages/nbformat/__init__.py", line 143, in read
    return reads(buf, as_version, **kwargs)
  File "/home/circleci/project/venv/lib/python3.7/site-packages/nbformat/__init__.py", line 73, in reads
    nb = reader.reads(s, **kwargs)
  File "/home/circleci/project/venv/lib/python3.7/site-packages/nbformat/reader.py", line 58, in reads
    nb_dict = parse_json(s, **kwargs)
  File "/home/circleci/project/venv/lib/python3.7/site-packages/nbformat/reader.py", line 17, in parse_json
    raise NotJSONError(("Notebook does not appear to be JSON: %r" % s)[:77] + "...") from e
nbformat.reader.NotJSONError: Notebook does not appear to be JSON: '{\n  "nbformat": 4,\n  "nbformat_minor"...

make: *** [Makefile:43: html] Error 2