code: def check_installed_debian(pkgname):
      
      import utool as ut
      #pkgname = 'espeak'
      #pkgname = 'sudo'
      #ut.cmd('hash ' + pkgname + ' 2>/dev/null')
      tup = ut.cmd('hash ' + pkgname + ' 2>/dev/null', quiet=True, pad_stdout=False)
      out, err, ret = tup
      is_installed = (ret == 0)
      return is_installed
docs: References:
          http://www.cyberciti.biz/faq/find-out-if-package-is-installed-in-linux/