def node_threat(n_risk, cta, threat_type='Generic', threat_horizon='day',
    threat_credibility='1'):
    """
    This function calculates the threat at each node
    :param threat_horizon: options: day (default, hour, two_day, week, two_week, month, few-months, year)
    :param threat_credibility: min: 0, max: 1 (default).
    :param n_risk:
    :param threat_type: default value is Generic, other possible values can be based on event.
    :param cta: closest_threat_anchor: A tuple containing lat, long of a threat anchor
    :return: node_threat_value
    """
    node_threat_value = 0
    return node_threat_value
