Is there a way to change the closure of a python function?

[Jussi Piitulainen]

Chris Angelico writes:

> On Wed, Sep 28, 2016 at 7:19 AM, Terry Reedy wrote:
>> The value of the cell variable is writable from within the body of the
>> closure function if declared nonlocal, but not otherwise, and not from
>> without.  The latter may be what Peng meant by 'change' and the blogger by
>> 'read-only'.
>>
>
> Not from entirely without, but it's possible for two functions to
> share a cell. I don't know the mechanics of how nonlocal assignment
> works, but ultimately, it's updating the cell that both closures see,
> so it's going to affect the other function too.

Standard example:

def make():
    def inquire():
        return balance
    def deposit(amount):
        nonlocal balance
        balance += amount
    def withdraw(amount):
        nonlocal balance
        balance -= amount
    balance = 0
    return inquire, deposit, withdraw

inq1, put1, get1 = make()
inq2, put2, get2 = make()

put1(30) ; get1(10) ; put1(40)
put2(500) ; put2(500) ; put2(500)

assert inq1() == 60
assert inq2() == 1500