How to use the cffi.model.PrimitiveType function in cffi

def test_cffi_opcode_sync():
    import cffi.model
    for name in dir(lib):
        if name.startswith('_CFFI_'):
            assert getattr(cffi_opcode, name[6:]) == getattr(lib, name)
    assert sorted(cffi_opcode.PRIMITIVE_TO_INDEX.keys()) == (
        sorted(cffi.model.PrimitiveType.ALL_PRIMITIVE_TYPES.keys()))

def test_primitive_category():
    for typename in all_primitive_types:
        tp = model.PrimitiveType(typename)
        C = tp.is_char_type()
        F = tp.is_float_type()
        X = tp.is_complex_type()
        I = tp.is_integer_type()
        assert C == (typename in ('char', 'wchar_t', 'char16_t', 'char32_t'))
        assert F == (typename in ('float', 'double', 'long double'))
        assert X == (typename in ('float _Complex', 'double _Complex'))
        assert I + F + C + X == 1      # one and only one of them is true

def test_primitive_category():
    for typename in all_primitive_types:
        tp = model.PrimitiveType(typename)
        C = tp.is_char_type()
        F = tp.is_float_type()
        X = tp.is_complex_type()
        I = tp.is_integer_type()
        assert C == (typename in ('char', 'wchar_t', 'char16_t', 'char32_t'))
        assert F == (typename in ('float', 'double', 'long double'))
        assert X == (typename in ('float _Complex', 'double _Complex'))
        assert I + F + C + X == 1      # one and only one of them is true

else:
        assert abs(more_precise - less_precise) > 0.1
        # Check the particular results on Intel
        import platform
        if (platform.machine().startswith('i386') or
            platform.machine().startswith('i486') or
            platform.machine().startswith('i586') or
            platform.machine().startswith('i686') or
            platform.machine().startswith('x86')):
            assert abs(more_precise - 0.656769) < 0.001
            assert abs(less_precise - 3.99091) < 0.001
        else:
            py.test.skip("don't know the very exact precision of 'long double'")


all_primitive_types = model.PrimitiveType.ALL_PRIMITIVE_TYPES
if sys.platform == 'win32':
    all_primitive_types = all_primitive_types.copy()
    del all_primitive_types['ssize_t']
all_integer_types = sorted(tp for tp in all_primitive_types
                           if all_primitive_types[tp] == 'i')
all_float_types = sorted(tp for tp in all_primitive_types
                            if all_primitive_types[tp] == 'f')

def all_signed_integer_types(ffi):
    return [x for x in all_integer_types if int(ffi.cast(x, -1)) < 0]

def all_unsigned_integer_types(ffi):
    return [x for x in all_integer_types if int(ffi.cast(x, -1)) > 0]


def test_primitive_category():