If you see a "Bad magic number" error in the terminal or console window when trying to start Calypso, this means you are running a Python version that is incompatible with Calypso.Calypso currently requires Python 3.5.2. The installer provides this. But if you bypass the installer or subsequently override the Python installation to force a different version, you will not be able to run Calypso.The simplest fix for this problem is to run the installer again and allow it to install the version of Python required by Calypso.