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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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global SERVICE_PORTS, CONFIG_ENV_VARS
    SERVICE_PORTS = service_ports or parse_service_ports()
    globs = globals()
    
    for key, value in six.iteritems(DEFAULT_SERVICE_PORTS):
        key_upper = key.upper().replace('-', '_')
        
        port_var_name = 'PORT_%s' % key_upper
        port_number = service_port(key)
        globs[port_var_name] = port_number
        url = 'http%s://%s:%s' % ('s' if USE_SSL else '', LOCALSTACK_HOSTNAME, port_number)
        
        url_key = 'TEST_%s_URL' % key_upper
        globs[url_key] = url
        
        os.environ[url_key] = url
    
    os.environ['LOCALSTACK_HOSTNAME'] = LOCALSTACK_HOSTNAME
    
    CONFIG_ENV_VARS += ['LOCALSTACK_' + v for v in CONFIG_ENV_VARS if not v.startswith('LOCALSTACK_')]
    CONFIG_ENV_VARS = list(set(CONFIG_ENV_VARS))
def service_port(service_key):