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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 _random_id(self, size=16, chars=string.ascii_uppercase + string.digits):
 """ Generates a random id based on `size` and `chars` variable. By default it will generate a 16 character long string based on ascii uppercase letters and digits. """

        return ''.join(random.choice(chars) for _ in range(size))