[android] not finding android sdk (Unity)

1- Just open https://developer.android.com/studio/index.html

2- scroll down to the bottom of that page

3- download last version of tools for your OS (for example tools_r25.2.3-windows.zip)

4- Unzip it

5- Delete folder tools from previous Android Sdk folder

6- Copy new folder tools to Android SDK Folder like this image:

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