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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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super(LambdaExecutorSeparateContainers, self).__init__()
        self.next_port = 1
        self.max_port = LAMBDA_API_UNIQUE_PORTS
        self.port_offset = LAMBDA_API_PORT_OFFSET
    def prepare_event(self, environment, event_body):
        
        environment['DOCKER_LAMBDA_USE_STDIN'] = '1'
        return event_body.encode()
    def prepare_execution(self, func_arn, env_vars, runtime, command, handler, lambda_cwd):
        entrypoint = ''
        if command:
            entrypoint = ' --entrypoint ""'
        else:
            command = '"%s"' % handler
        
        network = config.LAMBDA_DOCKER_NETWORK
        network_str = '--network="%s"' % network if network else ''
        if network == 'host':
            port = str(self.next_port + self.port_offset)
            env_vars['DOCKER_LAMBDA_API_PORT'] = port
            env_vars['DOCKER_LAMBDA_RUNTIME_PORT'] = port
            self.next_port = (self.next_port + 1) % self.max_port
        env_vars_string = ' '.join(['-e {}="${}"'.format(k, k) for (k, v) in env_vars.items()])