{
    "first_name":   { "length_equal": 5 },
    "last_name":    { "length_equal": [6] },
    "middle_name": [{ "length_equal": [9] }],
    "number1":      { "length_equal": 4 },
    "empty_name":   { "length_equal": 3 },
    "missed_name":  { "length_equal": 3 }
}