SelectIndentOn() function for VIM to select all the lines with the same indent level in Python

.vimrc

" Inspired by https://vim.fandom.com/wiki/Visual_selection_of_indent_block
" This version additionaly goes through empty lines to select also separated blocks 
"   on the same indent level.
function SelectIndentOn()
  let temp_var=indent(line("."))
  if temp_var is 0 |  return | endif

  while (line(".") > 1) &&
      \ ((indent(line(".")-1) >= temp_var) || (getline(line(".")-1) is ""))
    exe "normal k"
  endwhile
  let empty_lines = 0
  exe "normal V"
  while (line(".") < line("$")) &&
      \ ((indent(line(".")+1) >= temp_var) || (getline(line(".")+1) is ""))
    exe "normal j"

    if getline(line(".")) is ""
      let empty_lines += 1
    else
      let empty_lines = 0
    endif
  endwhile
  if empty_lines > 0 | exe "normal " . empty_lines . "k" | endif
  exe "normal ^"
endfun
noremap <F5> :call SelectIndentOn()<CR>