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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_ipv4_address_from_subnet(self, subnet, network=False):
 """ Produces a random IPv4 address or network with a valid CIDR from within a given subnet. :param subnet: IPv4Network to choose from within :param network: Return a network address, and not an IP address """

        address = str(
            subnet[self.generator.random.randint(
                0, subnet.num_addresses - 1,
            )],
        )

        if network:
            address += '/' + str(self.generator.random.randint(
                subnet.prefixlen,
                subnet.max_prefixlen,
            ))
            address = str(ip_network(address, strict=False))

        return address