Local Scope.

Third class. Variables created inside a function are local — they live only while the function runs.

x = 10

def bump():
    x = 1
    return x

print(bump())  # 1
print(x)       # 10 — the outer x did not change

The assignment x = 1 inside creates a new local x. That does not touch the global x unless you use global (we do not learn that today).

Common mistake: expecting an outer variable to change from an inner assignment; or reading a local before it exists.