exec in a nested function yields an error

[TP]

Hi everybody,

Try the following program:

####################
def f():
    def f_nested():
        exec "a=2"
        print a
f()
####################

It yields an error.
$ python nested_exec.py
  File "nested_exec.py", line 3
    exec "a=2"
SyntaxError: unqualified exec is not allowed in function 'f_nested' it is a
nested function

What is the problem?
Why?

Thanks

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