I am using the **latest** localstack docker image to test aws s3, lambda and cloudformation locally. s3 and lambda seems to be working fine but when I call cloudformation **create-stack** api it gives me a 502 BadGateway error. This is the command I am using

`aws cloudformation create-stack \
  --template-body template.yaml \
  --stack-name cfn-test \
  --parameters ParameterKey=BucketPrefix,ParameterValue=demo-bucket \
  --endpoint-url=http://localhost:4581`

This is the error I get:
`An error occurred (502) when calling the CreateStack operation (reached max retries: 4): Bad Gateway`

From docker logs I got the following error
`2019-12-31T22:12:09:ERROR:localstack.services.generic_proxy: Error forwarding request: 'str' object has no attribute 'get' Traceback (most recent call last):
  File "/opt/code/localstack/localstack/services/generic_proxy.py", line 242, in forward
    path=path, data=data, headers=forward_headers)
  File "/opt/code/localstack/localstack/services/cloudformation/cloudformation_listener.py", line 164, in forward_request
    modified_request = transform_template(req_data)
  File "/opt/code/localstack/localstack/services/cloudformation/cloudformation_listener.py", line 83, in transform_template
    if parsed.get('Transform') == 'AWS::Serverless-2016-10-31':
AttributeError: 'str' object has no attribute 'get'`

Although, when I try the **list-stacks** api it seems to be working fine
`aws --endpoint-url=http://localhost:4581 cloudformation list-stacks`

`{
    "StackSummaries": []
}`

`2019-12-31 22:10:51,865:API: 127.0.0.1 - - [31/Dec/2019 22:10:51] "GET / HTTP/1.1" 200 -`

I could not find a solution in any of the past issues or anywhere on the internet. Please assist
},
    'Kinesis::Stream': {
        'create': {
            'function': 'create_stream',
            'parameters': {
                'StreamName': 'Name',
                'ShardCount': 'ShardCount'
            },
            'defaults': {
                'ShardCount': 1
            }
        },
        'delete': {
            'function': 'delete_stream',
            'parameters': {
                'StreamName': 'PhysicalResourceId'
            }
        }
    },
    'StepFunctions::StateMachine': {
        'create': {
            'function': 'create_state_machine',
            'parameters': {
                'name': ['StateMachineName', PLACEHOLDER_RESOURCE_NAME],
                'definition': 'DefinitionString',
                'roleArn': lambda params, **kwargs: get_role_arn(params.get('RoleArn'), **kwargs)
            }
        }
    },
    'StepFunctions::Activity': {