def get_with_refresh_token(refresh_token, resource = nil)
      logger.verbose('TokenRequest getting token with refresh token digest ' \
                     "#{Digest::SHA256.hexdigest refresh_token} and resource " \
                     "#{resource}.")
      request_no_cache(GRANT_TYPE => GrantType::REFRESH_TOKEN,
                       REFRESH_TOKEN => refresh_token,
                       RESOURCE => resource)
    end
def get_with_refresh_token(refresh_token, resource = nil)
      logger.verbose('TokenRequest getting token with refresh token digest ' \
                     "#{Digest::SHA256.hexdigest refresh_token} and resource " \
                     "#{resource}.")
      request_no_cache(GRANT_TYPE => GrantType::REFRESH_TOKEN,
                       REFRESH_TOKEN => refresh_token,
                       RESOURCE => resource)
    end
Gets a token based on a previously acquired refresh token.

 @param String refresh_token
   The refresh token that was previously acquired from a token response.
 @optional String resource
   The resource for which the requested access token will provide access.
 @return TokenResponse