import json


def get_netsel_urls(netsel_file):
    """Return list of CSK urls."""

    # use sorted list of urls of the InSAR inputs to create hash
    with open(netsel_file) as f:
        netsel_json = json.load(f)
    urls = []
    for i in netsel_json:
        for j in i: urls.append(j['url'])
    return urls