same var name as function name in nodejs

I am a bit confused with the code below, can we create class in js this way?

module.exports = function testname(paramas){
  testname.test = function(req, res){
  //some code here
  }
  return testname;
}

should not we use this.test instead of function name.test?

ClassName.methodname creates static members, while this.methodname creates instance members

function MyClass () {
  this.fn = function () {
    // instance member function
  }
}

MyClass.anotherFn = function () {
  // Static member function
}

If you want to create some variables which should be encapsulated within the class objects when you create them, use this.var.

However, if you want a data member to be shared among all the instances of the same class then use ClassName.var