Type annotations for boto3 Batch

import boto3
from typing import TYPE_CHECKING

if TYPE_CHECKING:
    from mypy_boto3_batch.client import BatchClient
    from mypy_boto3_batch.type_defs import DescribeJobQueuesResponseTypeDef

    # Example of a Paginator import
    from mypy_boto3_batch.paginators import ListJobsPaginator


def get_batch_client() -> 'BatchClient':
    """Returns a type-hinted boto3 Batch client."""
    return boto3.client("batch")


def describe_queues() -> 'DescribeJobQueuesResponseTypeDef':
    """Describes Batch job queues with type hints."""
    client: BatchClient = get_batch_client()
    response = client.describe_job_queues()
    print(f"Job Queues: {len(response['jobQueues'])}")
    return response


def list_all_jobs():
    """Lists all jobs using a paginator with type hints."""
    client: BatchClient = get_batch_client()
    paginator: ListJobsPaginator = client.get_paginator('list_jobs')
    for page in paginator.paginate(jobQueue='example-queue'): # Replace 'example-queue' with an actual queue
        for job in page.get('jobSummaryList', []):
            print(f"Job ID: {job['jobId']}, Name: {job['jobName']}")

# Example usage (requires AWS credentials and an existing Batch setup)
if __name__ == '__main__':
    # This code will execute if you have AWS credentials configured
    # and an AWS Batch environment. For type checking, no actual AWS call is needed.
    # To run this, ensure boto3 is configured, e.g., via AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY, AWS_REGION
    # Or by using 'aws configure'
    try:
        queues_response = describe_queues()
        # You can add more complex logic here
        # list_all_jobs() # Uncomment to test paginator, requires a valid jobQueue
    except Exception as e:
        print(f"Error interacting with AWS Batch (this is expected if AWS credentials/resources are not set up): {e}")