Who can help me with this error? E / AndroidRuntime: FATAL EXCEPTION: main

I'm starting in the world of kotlin and when I say starting is that I'm watching all kinds of tutorials, from My First App in Android Developer, through YouTube and other tutorials, on a particular page link explain how to read an existing BD and I was thrilled to replicate it, it's a basic code of reading a BD in the assets / databases folder and when executing it in the androidStudio emulator, it gives me this message:

Here is the structure of the project that shows the location of the database:

Here is the code I used:

MainActivity.kt

package com.example.example

import android.os.Bundle
import android.support.v7.app.AppCompatActivity

class MainActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        // This is an example, remember to use a background thread in production.
        val myDatabase = MyDatabaseHelper(this).readableDatabase

        myDatabase.rawQuery("SELECT * FROM Region", null)
    }
}

MyDatabaseHelper.kt

package com.example.example

import android.content.Context
import android.content.SharedPreferences
import android.database.sqlite.SQLiteDatabase
import android.database.sqlite.SQLiteOpenHelper
import java.io.File
import java.io.FileOutputStream

class MyDatabaseHelper(val context: Context) : SQLiteOpenHelper(context,         DATABASE_NAME, null, DATABASE_VERSION) {

private val preferences: SharedPreferences = context.getSharedPreferences(
        "${context.packageName}.database_versions",
        Context.MODE_PRIVATE
)

private fun installedDatabaseIsOutdated(): Boolean {
    return preferences.getInt(DATABASE_NAME, 0) < DATABASE_VERSION
}

private fun writeDatabaseVersionInPreferences() {
    preferences.edit().apply {
        putInt(DATABASE_NAME, DATABASE_VERSION)
        apply()
    }
}

private fun installDatabaseFromAssets() {
    val inputStream = context.assets.open("$ASSETS_PATH/$DATABASE_NAME.sqlite3")

    try {
        val outputFile = File(context.getDatabasePath(DATABASE_NAME).path)
        val outputStream = FileOutputStream(outputFile)

        inputStream.copyTo(outputStream)
        inputStream.close()

        outputStream.flush()
        outputStream.close()
    } catch (exception: Throwable) {
        throw RuntimeException("The $DATABASE_NAME database couldn't be installed.", exception)
    }
}

@Synchronized
private fun installOrUpdateIfNecessary() {
    if (installedDatabaseIsOutdated()) {
        context.deleteDatabase(DATABASE_NAME)
        installDatabaseFromAssets()
        writeDatabaseVersionInPreferences()
    }
}

override fun getWritableDatabase(): SQLiteDatabase {
    throw RuntimeException("The $DATABASE_NAME database is not writable.")
}

override fun getReadableDatabase(): SQLiteDatabase {
    installOrUpdateIfNecessary()
    return super.getReadableDatabase()
}

override fun onCreate(db: SQLiteDatabase?) {
    // Nothing to do
}

override fun onUpgrade(db: SQLiteDatabase?, oldVersion: Int, newVersion: Int) {
    // Nothing to do
}

companion object {
    const val ASSETS_PATH = "databases"
    const val DATABASE_NAME = "mydb"
    const val DATABASE_VERSION = 1
}

}

Here is the exit of Logcat :

E/AndroidRuntime: FATAL EXCEPTION: main
              Process: com.example.example, PID: 5700
              java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.example/com.example.example.MainActivity}: java.lang.RuntimeException: The mydb database couldn't be installed.
                  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2325)
                  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2387)
                  at android.app.ActivityThread.access$800(ActivityThread.java:151)
                  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1303)
                  at android.os.Handler.dispatchMessage(Handler.java:102)
                  at android.os.Looper.loop(Looper.java:135)
                  at android.app.ActivityThread.main(ActivityThread.java:5254)
                  at java.lang.reflect.Method.invoke(Native Method)
                  at java.lang.reflect.Method.invoke(Method.java:372)
                  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
                  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
               Caused by: java.lang.RuntimeException: The mydb database couldn't be installed.
                  at com.example.example.MyDatabaseHelper.installDatabaseFromAssets(MyDatabaseHelper.kt:41)
                  at com.example.example.MyDatabaseHelper.installOrUpdateIfNecessary(MyDatabaseHelper.kt:49)
                  at com.example.example.MyDatabaseHelper.getReadableDatabase(MyDatabaseHelper.kt:59)
                  at com.example.example.MainActivity.onCreate(MainActivity.kt:12)
                  at android.app.Activity.performCreate(Activity.java:5990)
                  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1106)
                  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2278)
                  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2387) 
                  at android.app.ActivityThread.access$800(ActivityThread.java:151) 
                  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1303) 
                  at android.os.Handler.dispatchMessage(Handler.java:102) 
                  at android.os.Looper.loop(Looper.java:135) 
                  at android.app.ActivityThread.main(ActivityThread.java:5254) 
                  at java.lang.reflect.Method.invoke(Native Method) 
                  at java.lang.reflect.Method.invoke(Method.java:372) 
                  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903) 
                  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698) 
               Caused by: java.io.FileNotFoundException: /data/data/com.example.example/databases/mydb: open failed: ENOENT (No such file or directory)
                  at libcore.io.IoBridge.open(IoBridge.java:456)
                  at java.io.FileOutputStream.<init>(FileOutputStream.java:87)
                  at java.io.FileOutputStream.<init>(FileOutputStream.java:72)
                  at com.example.example.MyDatabaseHelper.installDatabaseFromAssets(MyDatabaseHelper.kt:33)
                  at com.example.example.MyDatabaseHelper.installOrUpdateIfNecessary(MyDatabaseHelper.kt:49) 
                  at com.example.example.MyDatabaseHelper.getReadableDatabase(MyDatabaseHelper.kt:59) 
                  at com.example.example.MainActivity.onCreate(MainActivity.kt:12) 
                  at android.app.Activity.performCreate(Activity.java:5990) 
                  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1106) 
                  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2278) 
                  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2387) 
                  at android.app.ActivityThread.access$800(ActivityThread.java:151) 
                  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1303) 
                  at android.os.Handler.dispatchMessage(Handler.java:102) 
                  at android.os.Looper.loop(Looper.java:135) 
                  at android.app.ActivityThread.main(ActivityThread.java:5254) 
                  at java.lang.reflect.Method.invoke(Native Method) 
                  at java.lang.reflect.Method.invoke(Method.java:372) 
                  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903) 
                  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698) 
               Caused by: android.system.ErrnoException: open failed: ENOENT (No such file or directory)
                  at libcore.io.Posix.open(Native Method)
                  at libcore.io.BlockGuardOs.open(BlockGuardOs.java:186)
                  at libcore.io.IoBridge.open(IoBridge.java:442)
                  at java.io.FileOutputStream.<init>(FileOutputStream.java:87) 
                  at java.io.FileOutputStream.<init>(FileOutputStream.java:72) 
                  at com.example.example.MyDatabaseHelper.installDatabaseFromAssets(MyDatabaseHelper.kt:33) 
                  at com.example.example.MyDatabaseHelper.installOrUpdateIfNecessary(MyDatabaseHelper.kt:49) 
                  at com.example.example.MyDatabaseHelper.getReadableDatabase(MyDatabaseHelper.kt:59) 
                  at com.example.example.MainActivity.onCreate(MainActivity.kt:12) 
                  at android.app.Activity.performCreate(Activity.java:5990) 
                  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1106) 
                  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2278) 
                  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2387) 
                  at android.app.ActivityThread.access$800(ActivityThread.java:151) 
                  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1303) 
                  at android.os.Handler.dispatchMessage(Handler.java:102) 
                  at android.os.Looper.loop(Looper.java:135) 
                  at android.app.ActivityThread.main(ActivityThread.java:5254) 
                  at java.lang.reflect.Method.invoke(Native Method) 
                  at java.lang.reflect.Method.invoke(Method.java:372) 
                  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903) 
                  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698) 
Application terminated.

Any ideas that can help me?