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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 is_subnet_source_fw(cls, tenant_id, subnet):
 """Check if the subnet is created as a result of any FW operation. """

        cfg = config.CiscoDFAConfig().cfg
        subnet = subnet.split('/')[0]
        in_sub_dict = cls.get_in_ip_addr(tenant_id)
        if not in_sub_dict:
            return False
        if in_sub_dict.get('subnet') == subnet:
            return True
        out_sub_dict = cls.get_out_ip_addr(tenant_id)
        if not out_sub_dict:
            return False
        if out_sub_dict.get('subnet') == subnet:
            return True
        dummy_sub = cfg.firewall.fw_service_dummy_ip_subnet
        dummy_sub = dummy_sub.split('/')[0]
        return subnet == dummy_sub