title: How to filter for a ManytoManyField with through in Django?
body: <p>Trying to filter through all protocol data sources with their specific datasources in Protocol.</p>
  
  <p>Tried to use this: ProtocolDataSource.objects.filter(protocol__data_sources=..., protocol__data_sources=...) but obviously this comes up with an error. The dots are the name of the data source.</p>