What's the meaning of the following code?

[exhuma]

In the function to collapse addresses, you "split IP addresses and networks": https://github.com/phihag/ipaddress/blob/master/ipaddress.py#L394

I don't quite understand why this is done? The function docs mention nothing about passing ip-addresses into the function. Only networks. So this seems a bit redundant... no?

A bit later, you de-duplicate the data. But that is already covered by the merge process as well. No? Redundant again?

[phihag]

Sorry for the late reply, but here it is:

First of all, this project is a mirror of Python 3's ipaddress, so the code in question is copied straight from there.

Since the function name is collapse_addresses and the first and only parameter is addresses, you can pass in addresses and networks alike. In any case, we must check that the caller has not mixed IPv4 and IPv6 objects, and that's what this code does.