def METHOD_NAME(self, foyer_fullerene):
    assert len(foyer_fullerene.atom_types) == 1
    assert "C" in foyer_fullerene.atom_types
    assert (
        sympify("r")
        in foyer_fullerene.atom_types["C"].independent_variables
    )
    assert foyer_fullerene.atom_types["C"].parameters[
        "sigma"
    ] == u.unyt_quantity(0.1, u.nm)
    assert foyer_fullerene.atom_types["C"].parameters[
        "epsilon"
    ] == u.unyt_quantity(0.1, u.kJ / u.mol)
    assert foyer_fullerene.atom_types["C"].mass == u.unyt_quantity(
        12.01, u.amu
    )
    assert foyer_fullerene.atom_types["C"].charge == u.unyt_quantity(
        0.0, u.coulomb
    )
    assert foyer_fullerene.atom_types["C"].description == "carbon"
    assert foyer_fullerene.atom_types["C"].definition == "[C;r5;r6]"
    assert foyer_fullerene.atom_types["C"].expression == sympify(
        "4*epsilon*(-sigma**6/r**6 + sigma**12/r**12)"
    )