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
return get_or_create_file(os.path.join(TMP_FOLDER, '.localstack'))
def get_machine_id():
    global MACHINE_ID
    if MACHINE_ID:
        return MACHINE_ID
    
    configs_map = {}
    config_file_tmp = get_config_file_tempdir()
    config_file_home = get_config_file_homedir()
    for config_file in (config_file_home, config_file_tmp):
        if config_file:
            local_configs = load_file(config_file)
            local_configs = json.loads(to_str(local_configs))
            configs_map[config_file] = local_configs
            if 'machine_id' in local_configs:
                MACHINE_ID = local_configs['machine_id']
                break
    
    if not configs_map:
        return PROCESS_ID
    
    if not MACHINE_ID:
        MACHINE_ID = short_uid()
    
    for config_file, configs in configs_map.items():
        configs['machine_id'] = MACHINE_ID
        save_file(config_file, json.dumps(configs))
    return MACHINE_ID
def get_process_id():