autocomplete a IN clausole with range of value in a column sheet

[2009luca]

I have in a column of sheet:

AAA
BBB
CCC
...

I need to loop all values(until the last cell is blank) and autocomplete a IN clasuole based the value in column ... and have:

My_instr=('AAA','BBB','CCC')

Possible?
Tks.

note:
My_instr as String

 

[SkipVought]

Yes, write a function to loop thru the list and concatenate a string.