Adding a command to Vim

I would try something like this in your .vimrc or your ftplugin/python_ft.vim

command Pyrun execute "!python %"
command Intpyrun execute "!python -i %"

Then :Pyrun and :Intpyrun should work

You could then map a function key to each

map <F5> :Pyrun<CR>
map <F6> :Intpyrun<CR>