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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_sg(app='', env='', region='', **_):
 """Destroy Security Group. Args: app (str):
 Spinnaker Application name. env (str):
 Deployment environment. region (str):
 Region name, e.g. us-east-1. Returns: True upon successful completion. """

    vpc = get_vpc_id(account=env, region=region)

    url = '{api}/securityGroups/{env}/{region}/{app}'.format(api=API_URL, env=env, region=region, app=app)
    payload = {'vpcId': vpc}
    security_group = requests.get(url, params=payload, verify=GATE_CA_BUNDLE, cert=GATE_CLIENT_CERT)

    if not security_group:
        LOG.info('Nothing to delete.')
    else:
        LOG.info('Found Security Group in %(region)s: %(name)s', security_group)

        destroy_request = get_template('destroy/destroy_sg.json.j2', app=app, env=env, region=region, vpc=vpc)
        wait_for_task(destroy_request)

    return True