code: def _passphrase_callback(passphrase):
      '''
      Returns a callback function used to supply a passphrase for private keys
      '''
      def f(*args):
          return salt.utils.stringutils.to_bytes(passphrase)
      return f _passphrase_callback(passphrase):
      '''
      Returns a callback function used to supply a passphrase for private keys
      '''
      def f(*args):
          return salt.utils.stringutils.to_bytes(passphrase)
      return f
docs: Returns a callback function used to supply a passphrase for private keys