def export_net_json(net, net_type, indent='no-indent'):
    """ export json string of dat """
    import json
    from copy import deepcopy
    if net_type == 'dat':
        exp_dict = deepcopy(net.dat)
        if type(exp_dict['mat']) is not list:
            exp_dict['mat'] = exp_dict['mat'].tolist()
            if 'mat_orig' in exp_dict:
                exp_dict['mat_orig'] = exp_dict['mat_orig'].tolist()
    elif net_type == 'viz':
        exp_dict = net.viz
    elif net_type == 'sim_row':
        exp_dict = net.sim['row']
    elif net_type == 'sim_col':
        exp_dict = net.sim['col']
    if indent == 'indent':
        exp_json = json.dumps(exp_dict, indent=2)
    else:
        exp_json = json.dumps(exp_dict)
    return exp_json
