Update for macOS Sierra 10.12.6 - Android Studio for Mac 2.3.3
Locate the sdkmanager file usually under:
/Users/YOUR_MAC_USER/Library/Android/sdk/tools/bin
./sdkmanager --licenses
Warning: File /Users/mtro.josevaler**strong text**io/.android/repositories.cfg
could not be loaded.
6 of 6 SDK package licenses not accepted.
Review licenses that have not been accepted (y/N)? Y
To validate the problem has gone just repeat the operation involved in the license issue.