Install Telegram desktop client for linux (x64).

    More infos:
      https://telegram.org
      https://desktop.telegram.org/

def telegram():
    '''Install Telegram desktop client for linux (x64).

    More infos:
      https://telegram.org
      https://desktop.telegram.org/
    '''
    if not exists('~/bin/Telegram', msg='Download and install Telegram:'):
        run('mkdir -p /tmp/telegram')
        run('cd /tmp/telegram  &&  wget https://telegram.org/dl/desktop/linux')
        run('cd /tmp/telegram  &&  tar xf linux')
        with warn_only():
            run('mv /tmp/telegram/Telegram  ~/bin')
        run('rm -rf /tmp/telegram')
    else:
        print('skip download, dir ~/bin/Telegram already exists')
    run('ln -snf ~/bin/Telegram/Telegram  ~/bin/telegram',
            msg="\nCreate executable 'telegram':")