Probably related to #1643 , but what appears to happen seems different (at least the error is).

From what I can see, the lambda executes successfully, but then fails to return the result, returning the following instead:
```json
{
    "Type": "Server",
    "message": "Error executing Lambda function arn:aws:lambda:ap-northeast-1:000000000000:function:service-stage-functionName: module 'botocore.errorfactory' has no attribute 'ResourceAlreadyExistsException' Traceback (most recent call last):\n  File \"/opt/code/localstack/localstack/services/awslambda/lambda_executors.py\", line 106, in _store_logs\n    logs_client.create_log_group(logGroupName=log_group_name)\n  File \"/opt/code/localstack/.venv/lib/python3.6/site-packages/botocore/client.py\", line 357, in _api_call\n    return self._make_api_call(operation_name, kwargs)\n  File \"/opt/code/localstack/.venv/lib/python3.6/site-packages/botocore/client.py\", line 661, in _make_api_call\n    raise error_class(parsed_response, operation_name)\nbotocore.errorfactory.ResourceAlreadyExistsException: An error occurred (ResourceAlreadyExistsException) when calling the CreateLogGroup operation: The specified log group already exists\n\nDuring handling of the above exception, another exception occurred:\n\nTraceback (most recent call last):\n  File \"/opt/code/localstack/localstack/services/awslambda/lambda_api.py\", line 339, in run_lambda\n    event, context=context, version=version, asynchronous=asynchronous)\n  File \"/opt/code/localstack/localstack/services/awslambda/lambda_executors.py\", line 81, in execute\n    return do_execute()\n  File \"/opt/code/localstack/localstack/services/awslambda/lambda_executors.py\", line 70, in do_execute\n    self._store_logs(func_details, log_output, invocation_time)\n  File \"/opt/code/localstack/localstack/services/awslambda/lambda_executors.py\", line 107, in _store_logs\n    except botocore.errorfactory.ResourceAlreadyExistsException:\nAttributeError: module 'botocore.errorfactory' has no attribute 'ResourceAlreadyExistsException'\n",
    "__type": "InternalFailure"
}
```

Looking at the localstack end I see the following log:

```
...(lambda execution log, SUCCESS etc)...
> REPORT RequestId: 00e1e000-0e00-000c-0000-8ccf00ab00ba	Duration: 52.74 ms	Billed Duration: 100 ms	Memory Size: 1536 MB	Max Memory Used: 5 MB	
> nohup: failed to run command 'python': No such file or directory
2019-10-25T11:46:25:WARNING:localstack.services.awslambda.lambda_api: Error executing Lambda function arn:aws:lambda:ap-northeast-1:000000000000:function:service-stage-functionName: module 'botocore.errorfactory' has no attribute 'ResourceAlreadyExistsException' Traceback (most recent call last):
  File "/opt/code/localstack/localstack/services/awslambda/lambda_executors.py", line 106, in _store_logs
    logs_client.create_log_group(logGroupName=log_group_name)
  File "/opt/code/localstack/.venv/lib/python3.6/site-packages/botocore/client.py", line 357, in _api_call
    return self._make_api_call(operation_name, kwargs)
  File "/opt/code/localstack/.venv/lib/python3.6/site-packages/botocore/client.py", line 661, in _make_api_call
    raise error_class(parsed_response, operation_name)
botocore.errorfactory.ResourceAlreadyExistsException: An error occurred (ResourceAlreadyExistsException) when calling the CreateLogGroup operation: The specified log group already exists

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/opt/code/localstack/localstack/services/awslambda/lambda_api.py", line 339, in run_lambda
    event, context=context, version=version, asynchronous=asynchronous)
  File "/opt/code/localstack/localstack/services/awslambda/lambda_executors.py", line 81, in execute
    return do_execute()
  File "/opt/code/localstack/localstack/services/awslambda/lambda_executors.py", line 70, in do_execute
    self._store_logs(func_details, log_output, invocation_time)
  File "/opt/code/localstack/localstack/services/awslambda/lambda_executors.py", line 107, in _store_logs
    except botocore.errorfactory.ResourceAlreadyExistsException:
AttributeError: module 'botocore.errorfactory' has no attribute 'ResourceAlreadyExistsException'
```

Will update if I am able to create an easily reproducible case!
from localstack import config
from localstack.utils.aws import aws_stack
from localstack.utils.common import (
    CaptureOutput, FuncThread, TMP_FILES, short_uid, save_file,
    to_str, run, cp_r, json_safe, get_free_tcp_port)
from localstack.services.install import INSTALL_PATH_LOCALSTACK_FAT_JAR
LAMBDA_EXECUTOR_JAR = INSTALL_PATH_LOCALSTACK_FAT_JAR
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_NODEJS = 'nodejs'
LAMBDA_RUNTIME_NODEJS610 = 'nodejs6.10'
LAMBDA_RUNTIME_NODEJS810 = 'nodejs8.10'
LAMBDA_RUNTIME_NODEJS10X = 'nodejs10.x'
LAMBDA_RUNTIME_JAVA8 = 'java8'
LAMBDA_RUNTIME_DOTNETCORE2 = 'dotnetcore2.0'
LAMBDA_RUNTIME_DOTNETCORE21 = 'dotnetcore2.1'
LAMBDA_RUNTIME_GOLANG = 'go1.x'
LAMBDA_RUNTIME_RUBY = 'ruby'
LAMBDA_RUNTIME_RUBY25 = 'ruby2.5'
LAMBDA_RUNTIME_CUSTOM_RUNTIME = 'provided'
LAMBDA_EVENT_FILE = 'event_file.json'
LAMBDA_SERVER_UNIQUE_PORTS = 500
LAMBDA_SERVER_PORT_OFFSET = 5000
LOG = logging.getLogger(__name__)
MAX_CONTAINER_IDLE_TIME_MS = 600 * 1000
class LambdaExecutor(object):
    """ Base class for Lambda executors. Subclasses must overwrite the _execute method """
    def __init__(self):