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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 _generate_ipaddressfield(self, **kwargs):
 """ Currently only IPv4 fields. """

        field = kwargs['field']
        if field.default != NOT_PROVIDED:
            return self._generate_field_with_default(**kwargs)
        num_octets = 4
        octets = [str(random.randint(0, 255)) for n in range(num_octets)]
        return '.'.join(octets)