Headers required to authenticate a request.

        Assumes your ``Context`` already has a authentication token,
        either provided explicitly or obtained by logging into the
        Splunk instance.

        :returns: A list of 2-tuples containing key and value

def _auth_headers(self):
        """Headers required to authenticate a request.

        Assumes your ``Context`` already has a authentication token,
        either provided explicitly or obtained by logging into the
        Splunk instance.

        :returns: A list of 2-tuples containing key and value
        """
        if self.token is _NoAuthenticationToken:
            return []
        else:
            # Ensure the token is properly formatted
            if self.token.startswith('Splunk '):
                token = self.token
            else:
                token = 'Splunk %s' % self.token
            return [("Authorization", token)]