problem with simple class code

[diegoraffo]

I'm havingg a problem with my code, I dont know why my code doesn't work. It works well when I use a string value to the condition variable, but not when I try to change a list.
Here is a copy of an example that works:

class Car(object):
    condition = "new"
    def __init__(self, color):
        self.color = color
    def drive(self):
        self.condition = "used"

chevy = Car("Blue")
print (chevy.condition) 
ford = Car("Red")
print (ford.condition)
chevy.drive()
print (chevy.condition)
print (ford.condition)

Result:

Output:
new
new
used
new

The ford condition is new as it shouldbe considerning the ford.drive() wasn't executed.
Now when i change the condition value for a list it doesnt work:

class Car(object):
    condition = ["0","0"]
    def __init__(self, color):
        self.color = color
    def drive(self):
        self.condition[0] = "1"

chevy = Car("Blue")
print (chevy.condition)
ford = Car("Red")
print (ford.condition)
chevy.drive()
print (chevy.condition)
print (ford.condition)

Output:
['0', '0']
['0', '0']
['1', '0']
['1', '0']

In this example the ford condition change despite the ford.drive()has not been executed.
Does anyone know why this happens?