I am having trouble calling a method inside of a constructor function I have made. Here is the function and my attempt to call it...

```js
var Cohort = function(program, campus, number, students){
    this.program = program,
    this.campus = campus,
    this.number = number,
    this.students = students,
    function sayName(){
        return `This cohort is called ${program}, ${campus}, ${number}.`
    },
    function takeAttendance(){
        return console.log(students)
    }
}

var cohort1 = new Cohort("w", "pr", 27, ['devin', 'ben', 'bob'])
var cohort2 = new Cohort('w', 'pr', 31, ["Brendan Eich", "Dan Abramov", "Wes Bos", "Kent Dodds"])

cohort1.sayName()
```

the console is saying cohort1.sayName is not a function.