How to use the vulture.utils.condition_is_always_true function in vulture

('foo or False', False, False),
        ('foo and True', False, False),
        ('foo or True', False, True),
        ('False and foo', True, False),
        ('False and 1', True, False),
        ('not False', False, True),
        ('not True', True, False),
        ('not foo', False, False),
        ('foo and (False or [])', True, False),
        ('(foo and bar) or {"a": 1}', False, True),
    ]
    for condition, always_false, always_true in conditions:
        condition = ast.parse(condition, mode='eval').body
        assert not (always_false and always_true)
        assert utils.condition_is_always_false(condition) == always_false
        assert utils.condition_is_always_true(condition) == always_true

def check_condition(code, result):
    condition = ast.parse(code, mode='eval').body
    if result:
        assert utils.condition_is_always_true(condition)
    else:
        assert utils.condition_is_always_false(condition)

def test_errors():
    conditions = [
        'foo',
        '__name__ == "__main__"',
        'chr(-1)',
        'getattr(True, "foo")',
        'hasattr(str, "foo")',
        'isinstance(True, True)',
        'globals()',
        'locals()',
        '().__class__',
    ]
    for condition in conditions:
        condition = ast.parse(condition, mode='eval').body
        assert not utils.condition_is_always_false(condition)
        assert not utils.condition_is_always_true(condition)

def _handle_conditional_node(self, node, name):
        if utils.condition_is_always_false(node.test):
            self._define(
                self.unreachable_code, name, node,
                last_node=node.body[-1],
                message="unsatisfiable '{name}' condition".format(**locals()),
                confidence=100)
        elif utils.condition_is_always_true(node.test):
            else_body = node.orelse
            if else_body:
                self._define(
                    self.unreachable_code, 'else', else_body[0],
                    last_node=else_body[-1],
                    message="unreachable 'else' block",
                    confidence=100)
            elif name == 'if':
                # Redundant if-condition without else block.
                self._define(
                    self.unreachable_code, name, node,
                    message="redundant if-condition".format(**locals()),
                    confidence=100)