Using custom theme file not working in NixOS

[ecribia]

Hi, im able to use the built in themes, but not a custom theme. Here is the output i get:

Traceback (most recent call last):
  File "/nix/store/r6589p0f23xq8jc7dm4ahwl3zwmxb5x3-python3.10-pywal-3.3.0/bin/.wal-wrapped", line 9, in <module>
    sys.exit(main())
  File "/nix/store/r6589p0f23xq8jc7dm4ahwl3zwmxb5x3-python3.10-pywal-3.3.0/lib/python3.10/site-packages/pywal/__main__.py", line 208, in main
    parse_args(parser)
  File "/nix/store/r6589p0f23xq8jc7dm4ahwl3zwmxb5x3-python3.10-pywal-3.3.0/lib/python3.10/site-packages/pywal/__main__.py", line 167, in parse_args
    colors_plain = theme.file(args.theme, args.l)
  File "/nix/store/r6589p0f23xq8jc7dm4ahwl3zwmxb5x3-python3.10-pywal-3.3.0/lib/python3.10/site-packages/pywal/theme.py", line 119, in file
    return parse(theme_file)
  File "/nix/store/r6589p0f23xq8jc7dm4ahwl3zwmxb5x3-python3.10-pywal-3.3.0/lib/python3.10/site-packages/pywal/theme.py", line 69, in parse
    data = util.read_file_json(theme_file)
  File "/nix/store/r6589p0f23xq8jc7dm4ahwl3zwmxb5x3-python3.10-pywal-3.3.0/lib/python3.10/site-packages/pywal/util.py", line 68, in read_file_json
    return json.load(json_file)
  File "/nix/store/pkj7cgmz66assy7l18zc7j992npb41nx-python3-3.10.12/lib/python3.10/json/__init__.py", line 293, in load
    return loads(fp.read(),
  File "/nix/store/pkj7cgmz66assy7l18zc7j992npb41nx-python3-3.10.12/lib/python3.10/json/__init__.py", line 346, in loads
    return _default_decoder.decode(s)
  File "/nix/store/pkj7cgmz66assy7l18zc7j992npb41nx-python3-3.10.12/lib/python3.10/json/decoder.py", line 337, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "/nix/store/pkj7cgmz66assy7l18zc7j992npb41nx-python3-3.10.12/lib/python3.10/json/decoder.py", line 355, in raw_decode
    raise JSONDecodeError("Expecting value", s, err.value) from None
json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)