Sometimes, attempting to run lambdas will return this type of error:
```
{"Type": "Server", "message": "Error executing Lambda function arn:aws:lambda:ap-northeast-1:000000000000:function:service-stage-functionName: An error occurred (ResourceAlreadyExistsException) when calling the CreateLogGroup operation: The specified log group already exists Traceback (most recent call last):\n 
File \"/opt/code/localstack/localstack/services/awslambda/lambda_api.py\", line 338, 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 105, 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)\n
botocore.errorfactory.ResourceAlreadyExistsException: An error occurred (ResourceAlreadyExistsException) when calling the CreateLogGroup operation: The specified log group already exists\n", "__type": "InternalFailure"}
```
I am not yet sure if there are any particular settings that cause it, since it does not occur for certain deployments.

Will update if I can figure out the exact configuration.
resource_id = resource_props['FunctionName'] if resource else resource_id
            return aws_stack.connect_to_service('lambda').get_function(FunctionName=resource_id)
        elif resource_type == 'Lambda::Version':
            name = resource_props['FunctionName']
            func_name = aws_stack.lambda_function_name(name)
            func_version = name.split(':')[7] if len(name.split(':')) > 7 else '$LATEST'
            versions = aws_stack.connect_to_service('lambda').list_versions_by_function(FunctionName=func_name)
            return ([v for v in versions['Versions'] if v['Version'] == func_version] or [None])[0]
        elif resource_type == 'Lambda::EventSourceMapping':
            resource_id = resource_props['FunctionName'] if resource else resource_id
            source_arn = resource_props.get('EventSourceArn')
            resource_id = resolve_refs_recursively(stack_name, resource_id, resources)
            source_arn = resolve_refs_recursively(stack_name, source_arn, resources)
            if not resource_id or not source_arn:
                raise Exception('ResourceNotFound')
            mappings = aws_stack.connect_to_service('lambda').list_event_source_mappings(
                FunctionName=resource_id, EventSourceArn=source_arn)
            mapping = list(filter(lambda m:
                m['EventSourceArn'] == source_arn and m['FunctionArn'] == aws_stack.lambda_function_arn(resource_id),
                mappings['EventSourceMappings']))
            if not mapping:
                raise Exception('ResourceNotFound')
            return mapping[0]
        elif resource_type == 'DynamoDB::Table':
            resource_id = resource_props['TableName'] if resource else resource_id
            return aws_stack.connect_to_service('dynamodb').describe_table(TableName=resource_id)
        elif resource_type == 'ApiGateway::RestApi':
            apis = aws_stack.connect_to_service('apigateway').get_rest_apis()['items']
            resource_id = resource_props['Name'] if resource else resource_id
            result = list(filter(lambda api: api['name'] == resource_id, apis))