Creating a file with variable name but distinct extension

[Moeniac]

Hello everybody,
for my current homework i need to create an amount of *.csv files, however the filename must be taken from a list that is provided as a *.txt-document .
i succesfully wrote a code that takes the right string out of the provided *txt, i fail to write the code correctly so it adds the file extension.


right now it looks like this

"with open(namefromtxt,".csv","w")as csv:"

thanks in advance from germany

Moeniac