How to urlencode a json payload with empty key values and parse it to get the original payload

Question

All I'm trying to do is urlencode the payload and then parse it to get what I originally started with.

payload = {"contact_uuid": "67460e74-02e3-11e8-b443-00163e990bdb", "choices": None, "value": "", "cardType": "", "step": None, "optionId": None, "path": "", "title": "", "description": "", "message": ""}

urlencode(payload) returns:

contact_uuid=67460e74-02e3-11e8-b443-00163e990bdb&choices=None&value=&cardType=&step=None&optionId=None&path=&title=&description=&message=

Notice the empty strings are lost

When I try to parse it back to the original json it doesn't work (variable name is encoded_url)

body = (parse_qs(encoded_payload))

print(body) returns:

{'contact_uuid': ['67460e74-02e3-11e8-b443-00163e990bdb'], 'choices': ['None'], 'step': ['None'], 'optionId': ['None']}

Please how can I urlencode the original payload without losing empty key values and then parse it to get the original json payload. I also do not want the lists. I just want the exact json form I started with. NB - It doesn't have to be urlencode or parse libraries. Other solutions are welcome. Thanks