How can I change the Attribute within the parent class while keeping it working as the following figure in django

'''
#This is the parent class and I want to change the value of query_param from the child class #without affecting its work

class SearchMixin(object):
      query_param = "q"
      def get_query_param(self):
          return self.query_param    
      def get_query(self, request):
          return request.GET.get(self.get_query_param(), "").strip()    
      def get(self, request, *args, **kwargs):
          self.query = self.get_query(request)
          return super(SearchMixin, self).get(request, *args, **kwargs)
        
        
        
#child class I'm writing and it's not working
class SearchView_(SearchMixin):
      query_param = "qu"
      def get_query_param(self):
          SearchMixin.query_param = self.query_param
      def get_query(self, request):
          return request.GET.get(self.get_query_param(), "").strip() 
      def get(self, request, *args, **kwargs):
          self.get_query_param()
          self.query = self.get_query(request)
          return super(SearchView_, self).get(request, *args, **kwargs)

'''