Dyndns using multiple wan

Hi,

i am using 2 wan connections (one as failover - see https://wiki.mikrotik.com/wiki/Two_gateways_failover ) and want to use 2 dyndns account these.
Since the are double natted i use this to determine the external ip.

# get the current IP address from the internet (in case of double-nat)
/tool fetch mode=http address="checkip.dyndns.org" src-path="/" dst-path="/dyndns.checkip.html"
:delay 1
:local result [/file get dyndns.checkip.html contents]

But how can i send one fetch over wan1 and another fetch over wan2 to determine both ips?

BR

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