MongoDB import command does not import documents version 42.14

Working with Data Developer Tools
11

I know that file is valid ,
If you know that how to check valid file and let me know

test.json will be created when all documents once imported target file

Please watch the video ,

https://university.mongodb.com/mercury/M001/2021_August_10/chapter/Chapter_1_What_is_MongoDB_/lesson/5f32c8a304e9ffbb03b169ac/lecture

you have asked file size if there is one or more documents consisting in single collection when you start mongoimport all documents will be importing in target file

rs1:PRIMARY> db.test1.find().count()
4
rs1:PRIMARY> db.test1.find().size()
4
rs1:PRIMARY> db.test1.stats()
{
“ns” : “sample.test1”,
“size” : 207,
“count” : 4,
“avgObjSize” : 51,
“storageSize” : 36864,
“capped” : false,
“wiredTiger” : {
“metadata” : {
“formatVersion” : 1

In MongoDB old version 3.0 working mongoimport but new version getting error.