What is the difference between a class variable and an instance variable?

Question

Accepted Answer

**Class variable** is shared between all instances. **Instance variable** is unique to each instance.

```python
class User:
    # Class variable
    role = "user"

def __init__(self, name):
        # Instance variable
        self.name = name

u1 = User("Alice")
u2 = User("Bob")

print(u1.name)  # "Alice"
print(u2.name)  # "Bob"
print(u1.role)  # "user"
print(u2.role)  # "user"

# Changing class variable
User.role = "admin"
print(u1.role)  # "admin"
print(u2.role)  # "admin"
```

Python: What is the difference between a class variable and an instance variable?