def test_Stack_isEmpty_not_empty():
my_stack = Stack()
my_stack.push(1)
my_stack.push(2)
my_stack.push(3)
actual = my_stack.is_empty()
expected = False
assert actual == expected
def test_Stack_isEmpty_empty():
my_stack = Stack()
actual = my_stack.is_empty()
expected = True
assert actual == expected