(self, request, model_admin)
return (("yes", "Has a source"), ("no", "Has no source"))
Return a list of tuples.

        The first element in each tuple is the coded value for the option that will
        appear in the URL query. The second element is the
        human-readable name for the option that will appear
        in the right sidebar.
        source:
        https://docs.djangoproject.com/en/1.10/ref/contrib/admin/#django.contrib.admin.ModelAdmin.list_filter
Return a list of tuples.
Return a list of tuples .
def lookups(self, request, model_admin):
        """
        Return a list of tuples.

        The first element in each tuple is the coded value for the option that will
        appear in the URL query. The second element is the
        human-readable name for the option that will appear
        in the right sidebar.
        source:
        https://docs.djangoproject.com/en/1.10/ref/contrib/admin/#django.contrib.admin.ModelAdmin.list_filter
        """
        return (("yes", "Has a source"), ("no", "Has no source"))
def lookups ( self , request , model_admin ) : return ( ( "yes" , "Has a source" ) , ( "no" , "Has no source" ) )