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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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LAMBDA_EXECUTOR_CLASS = 'cloud.localstack.LambdaExecutor'
EVENT_FILE_PATTERN = '%s/lambda.event.*.json' % config.TMP_FOLDER
LAMBDA_RUNTIME_PYTHON27 = 'python2.7'
LAMBDA_RUNTIME_PYTHON36 = 'python3.6'
LAMBDA_RUNTIME_PYTHON37 = 'python3.7'
LAMBDA_RUNTIME_PYTHON38 = 'python3.8'
LAMBDA_RUNTIME_NODEJS = 'nodejs'
LAMBDA_RUNTIME_NODEJS43 = 'nodejs4.3'
LAMBDA_RUNTIME_NODEJS610 = 'nodejs6.10'
LAMBDA_RUNTIME_NODEJS810 = 'nodejs8.10'
LAMBDA_RUNTIME_NODEJS10X = 'nodejs10.x'
LAMBDA_RUNTIME_NODEJS12X = 'nodejs12.x'
LAMBDA_RUNTIME_JAVA8 = 'java8'
LAMBDA_RUNTIME_JAVA11 = 'java11'
LAMBDA_RUNTIME_DOTNETCORE2 = 'dotnetcore2.0'
LAMBDA_RUNTIME_DOTNETCORE21 = 'dotnetcore2.1'
LAMBDA_RUNTIME_DOTNETCORE31 = 'dotnetcore3.1'
LAMBDA_RUNTIME_GOLANG = 'go1.x'
LAMBDA_RUNTIME_RUBY = 'ruby'
LAMBDA_RUNTIME_RUBY25 = 'ruby2.5'
LAMBDA_RUNTIME_PROVIDED = 'provided'
LAMBDA_EVENT_FILE = 'event_file.json'
LAMBDA_SERVER_UNIQUE_PORTS = 500
LAMBDA_SERVER_PORT_OFFSET = 5000
LAMBDA_API_UNIQUE_PORTS = 500
LAMBDA_API_PORT_OFFSET = 9000
LOG = logging.getLogger(__name__)
MAX_CONTAINER_IDLE_TIME_MS = 600 * 1000
EVENT_SOURCE_SQS = 'aws:sqs'
def get_from_event(event, key):