Hi... I’m having a bit of a more fundamental question... sometimes, when using pip, the module is prefixed with python

Hi... I’m having a bit of a more fundamental question... sometimes, when using pip, the module is prefixed with python- (e.g. python-dateutil) while other times, it’s just the module name itself (e.g. selenium). Is there a logic here? Or do I need to hope I get the right package?