Problem with Installing Psychopy 2020 on MacOS Mojave 10.14.5

Hey there, thanks for reading this

I selected Standalone PsychoPy 2020.2.4 for macOS to download Psychopy. Everything goes well until I click on the downloaded file to open the programm.
My Mac says : ´ “StandalonePsychoPy-2020.2.4-macOS.dmg” cannot be opened because Apple cannot search for malware in it. This software must be updated. Contact the developer for more information.

Safari downloaded this file today at 12:36 from´

I have also downloaded the file from Google chrome but the same happens.
I hope you can help me:)

best regards,
Alexander Powol