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# Type of request: This is a ...

[x] bug report
[ ] feature request

# Detailed description
When `mountCode: true` for a serverless.yml deployment to localstack on Windows, Localstack mounts the wrong path.
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## Expected behavior
Docker expects the Windows client path value of the `-v` flag to begin with `/host_mtn/`.
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## Actual behavior
Localstack does not add this to the Windows client path. This causes the volume sharing to fail. Once one tries to invoke a lambda without the proper volume sharing, the lambda fails with an error along the lines of "can't find no module 'lambda_name'".
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# Steps to reproduce
1. In your `serverless.yml` set `mountCode: true` 
2. In your `docker-compose.yml` set the environment variable `LAMBDA_REMOTE_DOCKER: "0"` for the localstack container
3. Deploy some test lambda to the localstack container
4. Attempt to invoke with `awslocal lambda invoke --function-name LAMBDA_NAME out.txt` and replace LAMBDA_NAME with the name of your test lambda.
5. Note the invocation failure.

## Command used to start LocalStack
Started via a `docker-compose.yml` file. Pretty basic stuff.
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## Client code (AWS SDK code snippet, or sequence of "awslocal" commands)
Just the `awslocal` invoke command outlined above.
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return SERVICE_PORTS.get(service_key, 0)
def external_service_url(service_key, host=None):
    host = host or HOSTNAME_EXTERNAL
    return 'http%s://%s:%s' % ('s' if USE_SSL else '', host, service_port(service_key))
populate_configs()
if os.environ.get('DEBUG', '').lower() in TRUE_STRINGS:
    logging.getLogger('').setLevel(logging.DEBUG)
    logging.getLogger('localstack').setLevel(logging.DEBUG)
BUNDLE_API_PROCESSES = True
USE_PROFILER = os.environ.get('USE_PROFILER', '').lower() in TRUE_STRINGS