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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def wait_for_armable(self, timeout=None):
        '''Wait for the vehicle to become armable.

        If timeout is nonzero, raise a TimeoutError if the vehicle
        is not armable after timeout seconds.
        '''

        def check_armable():
            return self.is_armable

        self.wait_for(check_armable, timeout=timeout)