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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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""" Returns True if host responds to a ping request """
    is_windows = platform.system().lower() == 'windows'
    ping_opts = '-n 1' if is_windows else '-c 1'
    args = 'ping %s %s' % (ping_opts, host)
    return subprocess.call(args, shell=not is_windows, stdout=subprocess.PIPE, stderr=subprocess.PIPE) == 0
def in_docker():
    """ Returns True if running in a docker container, else False """
    if not os.path.exists('/proc/1/cgroup'):
        return False
    with open('/proc/1/cgroup', 'rt') as ifh:
        return 'docker' in ifh.read()
is_in_docker = in_docker()
is_in_linux = is_linux()
if not DOCKER_BRIDGE_IP:
    DOCKER_BRIDGE_IP = '172.17.0.1'
    if is_in_docker:
        candidates = (DOCKER_BRIDGE_IP, '172.18.0.1')
        for ip in candidates: