How to use numbers before a command in Vim?

Question

vim

Actually, how to make the number entered before pressing your own keyboard shortcut set not the number of repetitions, but something else.
For example, creating a for loop from zero to the entered digit should look something like this:

map <Number><A-m> Afor (int i = 0; i < <Number>; i++) {<Enter>

Outcome:

function! MyFor(v)
python <<EOF
import vim
v = vim.eval("a:v")
vim.current.line = vim.current.line + "for (int i = 0; i < " + v + "; i++) {"
EOF
endfunction
nnoremap <A-f> :<C-U>call MyFor(v:count)<CR>o<Esc>o}<Up><Tab>

Answer 1

Here , in the Supplying a count to a map section, it says that the number will be available through the v:count variable. There are also examples there.