moderated pending members to review



I just created a new group on io, and I am going to transfer my old Yahoo group onto it.

I have a question: I see a new pending member I do not know.

When Yahoo used to work, pending members would receive an automated email asking them to write a short presentation so I could check whether they correspond to the group's purpose. 

How can I set this in io groups ?

with many thanks

Deborah (Paris, France)

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