Unsuitable error when supplying an invalid instackenv.json

When running openstack overcloud node import instackenv.json with the following file I get: No JSON object could be decoded
{
    "nodes":[
        {
            "name": "controller-0",
            "mac":[
                "98:42:ab:a6:13:a2"
            ],
            "cpu":"18",
            "memory":"40000",
            "disk":"100",
            "arch":"x86_64",
            "pm_type":"pxe_ipmitool",
            "pm_user":"myuser",
            "pm_password":"mypassword",
            "pm_addr":"192.168.150.1"
        },
        {
            "name": "compute-0",
            "mac":[
                "98:42:ab:a6:13:1c"
            ],
            "cpu":"18",
            "memory":"40000",
            "disk":"100",
            "arch":"x86_64",
            "pm_type":"pxe_ipmitool",
            "pm_user":"myuser",
            "pm_password":"mypassword",
            "pm_addr":"192.168.150.2",
            "capabilities":"node:compute,boot_option:local"
        },
    ]
}

I expect the command to parse the file and tell where the error is.