# Buggy code
def sentry_handler(event, context, *args, **kwargs):
    # type: (Any, Any, *Any, **Any) -> Any
    hub = Hub.current
    integration = hub.get_integration(AwsLambdaIntegration)
    if integration is None:
        return handler(event, context, *args, **kwargs)

    # If an integration is there, a client has to be there.
    client = hub.client  # type: Any
    configured_time = context.get_remaining_time_in_millis()

    with hub.push_scope() as scope:
        with capture_internal_exceptions():
            scope.clear_breadcrumbs()
            scope.add_event_processor(
                _make_request_event_processor(event, context, configured_time)
            )
            scope.set_tag("aws_region", context.invoked_function_arn.split(":")[3])

            timeout_thread = None
            # Starting the Timeout thread only if the configured time is greater than Timeout warning
            # buffer and timeout_warning parameter is set True.
            if integration.timeout_warning and configured_time > TIMEOUT_WARNING_BUFFER:
                waiting_time = (
                    configured_time - TIMEOUT_WARNING_BUFFER
                ) / MILLIS_TO_SECONDS

                timeout_thread = TimeoutThread(
                    waiting_time,
                    configured_time / MILLIS_TO_SECONDS,
                )

                # Starting the thread to raise timeout warning exception
                timeout_thread.start()

        headers = event.get("headers", {})
        transaction = Transaction.continue_from_headers(
            headers, op="serverless.function", name=context.function_name
        )
        with hub.start_transaction(transaction):
            try:
                return handler(event, context, *args, **kwargs)
            except Exception:
                exc_info = sys.exc_info()
                event, hint = event_from_exception(
                    exc_info,
                    client_options=client.options,
                    mechanism={"type": "aws_lambda", "handled": False},
                )
                hub.capture_event(event, hint=hint)
                reraise(*exc_info)
            finally:
                if timeout_thread:
                    timeout_thread.stop()


# Traceback (AttributeError)
[ERROR] AttributeError: 'list' object has no attribute 'get'
Traceback (most recent call last):
File "/var/task/sentry_sdk/integrations/aws_lambda.py", line 106, in sentry_handler
headers = event.get("headers",
{}
)

# Fixed code
def sentry_handler(aws_event, context, *args, **kwargs):
    # type: (Any, Any, *Any, **Any) -> Any

    # Per https://docs.aws.amazon.com/lambda/latest/dg/python-handler.html,
    # `event` here is *likely* a dictionary, but also might be a number of
    # other types (str, int, float, None).
    #
    # In some cases, it is a list (if the user is batch-invoking their
    # function, for example), in which case we'll use the first entry as a
    # representative from which to try pulling request data. (Presumably it
    # will be the same for all events in the list, since they're all hitting
    # the lambda in the same request.)

    if isinstance(aws_event, list):
        request_data = aws_event[0]
        batch_size = len(aws_event)
    else:
        request_data = aws_event
        batch_size = 1

    if not isinstance(request_data, dict):
        # If we're not dealing with a dictionary, we won't be able to get
        # headers, path, http method, etc in any case, so it's fine that
        # this is empty
        request_data = {}

    hub = Hub.current
    integration = hub.get_integration(AwsLambdaIntegration)
    if integration is None:
        return handler(aws_event, context, *args, **kwargs)

    # If an integration is there, a client has to be there.
    client = hub.client  # type: Any
    configured_time = context.get_remaining_time_in_millis()

    with hub.push_scope() as scope:
        with capture_internal_exceptions():
            scope.clear_breadcrumbs()
            scope.add_event_processor(
                _make_request_event_processor(request_data, context, configured_time)
            )
            scope.set_tag("aws_region", context.invoked_function_arn.split(":")[3])
            if batch_size > 1:
                scope.set_tag("batch_request", True)
                scope.set_tag("batch_size", batch_size)

            timeout_thread = None
            # Starting the Timeout thread only if the configured time is greater than Timeout warning
            # buffer and timeout_warning parameter is set True.
            if integration.timeout_warning and configured_time > TIMEOUT_WARNING_BUFFER:
                waiting_time = (
                    configured_time - TIMEOUT_WARNING_BUFFER
                ) / MILLIS_TO_SECONDS

                timeout_thread = TimeoutThread(
                    waiting_time,
                    configured_time / MILLIS_TO_SECONDS,
                )

                # Starting the thread to raise timeout warning exception
                timeout_thread.start()

        headers = request_data.get("headers", {})
        transaction = Transaction.continue_from_headers(
            headers, op="serverless.function", name=context.function_name
        )
        with hub.start_transaction(transaction):
            try:
                return handler(aws_event, context, *args, **kwargs)
            except Exception:
                exc_info = sys.exc_info()
                sentry_event, hint = event_from_exception(
                    exc_info,
                    client_options=client.options,
                    mechanism={"type": "aws_lambda", "handled": False},
                )
                hub.capture_event(sentry_event, hint=hint)
                reraise(*exc_info)
            finally:
                if timeout_thread:
                    timeout_thread.stop()