We are having an issue with the latest image of localstack (bc991b0bc3ce).
While creating an SQS and setting parameters we experience the following error:

```
localstack_1        | 2019-09-09T10:46:22:ERROR:localstack.services.generic_proxy: Error forwarding request: 'QueueUrl' Traceback (most recent call last):
localstack_1        |   File "/opt/code/localstack/localstack/services/generic_proxy.py", line 234, in forward
localstack_1        |     path=path, data=data, headers=forward_headers)
localstack_1        |   File "/opt/code/localstack/localstack/services/sqs/sqs_listener.py", line 53, in forward_request
localstack_1        |     self._set_queue_attributes(req_data)
localstack_1        |   File "/opt/code/localstack/localstack/services/sqs/sqs_listener.py", line 245, in _set_queue_attributes
localstack_1        |     queue_url = req_data['QueueUrl'][0]
localstack_1        | KeyError: 'QueueUrl'
```

From the logs I guess the `QueueUrl` is expected and it's not there. We don't see this behaviour in the last version (0.10.2).

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""" Helper class to convert JSON documents with datetime, decimals, or bytes. """
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