Iteration over 0-d array upon passing interestRate

[anishzute]

If I attempt to call the optionsDF() or options() functions for an analytical query with the parameter interestRate = somefloat, it fails with TypeError: iteration over a 0-d array. If I comment out only the interestRate parameter, it runs flawlessly. The full code is below with the Traceback.

        option = tdc.optionsDF(strategy='ANALYTICAL',
                               symbol='SPY',
                               contractType='CALL'
                               strike=140,
                               fromDate='2020-05-20',
                               toDate='2020-05-21',
                               volatility=200,
                               underlyingPrice=240,
                               interestRate=0.1433,
                               daysToExpiration=5
                               )

File "...python3.7/site-packages/tdameritrade/client.py", line 405, in optionsDF
    optionType=optionType)
  File "...python3.7/site-packages/tdameritrade/client.py", line 369, in options
    return self._request(GET_OPTION_CHAIN, params=params).json()
  File "...python3.7/site-packages/tdameritrade/client.py", line 84, in _request
    resp = self.session.request(method, url, params=params, *args, **kwargs)
  File "...python3.7/site-packages/tdameritrade/session.py", line 22, in request
    return super().request(headers=self._headers, *args, **kwargs)
  File "...python3.7/site-packages/requests/sessions.py", line 516, in request
    prep = self.prepare_request(req)
  File "...python3.7/site-packages/requests/sessions.py", line 459, in prepare_request
    hooks=merge_hooks(request.hooks, self.hooks),
  File "...python3.7/site-packages/requests/models.py", line 314, in prepare
    self.prepare_url(url, params)
  File "...python3.7/site-packages/requests/models.py", line 432, in prepare_url
    enc_params = self._encode_params(params)
  File "...python3.7/site-packages/requests/models.py", line 100, in _encode_params
    for v in vs:
TypeError: iteration over a 0-d array