How does exec work with locals?

Question

I thought this would print 3, but it prints 1:

def f():
    a = 1
    exec(\"a = 3\")
    print(a)

Answer 1

If you are inside a method, you can do so:

class Thing():
    def __init__(self):
        exec('self.foo = 2')

x = Thing()
print(x.foo)

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