Error in creating a block

I created a block named ‘cost’. But it showing the error as in
screenshot attached what is the problem with this? thanks for your

Hi Vishwanatha,

you’ve forgot to modify your block’s XML description, which you can find
under /grc in your out of tree module.
I’d like to point you to the guided tutorials [1], which contain
information on that topic [2].

Best regards,


Hi Vishwanatha,

please stick to the list.

from gnuradio import project
ImportError: cannot import name project

indicates there is some line in your source code where you do that,
“from gnuradio import project”. Maybe you made a mistake in the
tag in your XML, maybe it’s in your source code.

I’d search for “from gnuradio import project” inside your source code,
and if that doesn’t yield where this happens, for “project”.