'is not serialised using json format' When using POST

[nclopezo]

I am trying to do a similarity search using POST, but I am getting the error:

<response><error_message>b'{"smiles": "CN1C(=O)C=C(c2cccc(Cl)c2)c3cc(ccc13)[C@@](N)(c4ccc(Cl)cc4)c5cncn5C", "similarity": 80}' is not serialised using json format</error_message></response>

You can see how to reproduce the error here:
https://colab.research.google.com/drive/1trPFQvY8xuew3aBUAirGOK2y0uL_3pxK