Features and examples:
threeML.test.test_UnresolvedExtendedXYLike.
get_signal
test_UnresolvedExtendedXYLike_assign_to_source
test_UnresolvedExtendedXYLike_chi2
test_UnresolvedExtendedXYLike_dataframe
test_UnresolvedExtendedXYLike_poisson
test_UnresolvedExtendedXYLike_txt
test_UnresolvedExtendedxy_plot