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# Type of request: This is a ...

[x] bug report
[ ] feature request

# Detailed description

In the `ReceiveMessageResult` of the SQS service, I saw this XML from localstack:

```
...
<MessageAttribute>
     <Name>encoding</Name>
    <Value>
        <DataType>String</DataType>
        <StringValue><![CDATA[gzip]]></StringValue>
    </Value>
</MessageAttribute>
...
```

The `<![CDATA[gzip]]>` is slightly different from AWS, which doesn't wrap the value in a `<!CDATA[[]]>` section. This shouldn't be a problem for XML parsers that accept both plain characters and CDATA sections for this element, but the XML parser I was using did not, which causes an error when running the code against localstack but not when running the code against AWS. There is obviously a bug in the XML parser as well, but I thought that I should at least post this here since it is different than what AWS SQS does.

## Expected behavior

MessageAttribute::Value elements should not be wrapped in `CDATA` sections.

## Actual behavior

MessageAttribute::Value elements all seem to be wrapped in `CDATA` sections.

# Steps to reproduce

Send a message to the SQS service which contains some custom message attributes, then make a ReceiveMessageRequest.

## Command used to start LocalStack

`docker run --env "SERVICES=sqs" localstack/localstack`

## Client code (AWS SDK code snippet, or sequence of "awslocal" commands)

...

0 if the container does not exist.
        """
        with self.docker_container_lock:
            
            container_name = self.get_container_name(func_arn)
            
            
            
            cmd = ("docker ps -a --filter name='%s' "
                   '--format "{{ .Status }} - {{ .Names }}" '
                   '| grep -w "%s" | cat') % (container_name, container_name)
            LOG.debug('Getting status for container "%s": %s' % (container_name, cmd))
            cmd_result = run(cmd)
            
            container_status = cmd_result.strip()
            if len(container_status) == 0:
                return 0
            if container_status.lower().startswith('up '):
                return 1
            return -1
    def get_docker_container_network(self, func_arn):
        """
        Determine the network of a docker container.
        :param func_arn: The ARN of the lambda function.
        :return: name of the container network
        """
        with self.docker_container_lock:
            status = self.get_docker_container_status(func_arn)
            
            if status == 0: