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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def destroy_cloudwatch_log_event(app='', env='dev', region=''):
 """Destroy Cloudwatch log event. Args: app (str):
 Spinnaker Application name. env (str):
 Deployment environment. region (str):
 AWS region. Returns: bool: True upon successful completion. """


    session = boto3.Session(profile_name=env, region_name=region)
    cloudwatch_client = session.client('logs')

    # FIXME: see below
    # TODO: Log group name is required, where do we get it if it is not in application-master-env.json?
    cloudwatch_client.delete_subscription_filter(logGroupName='/aws/lambda/awslimitchecker', filterName=app)

    return True