curl -X GET https://restapi.actonsoftware.com/api/1/list/l-ctx -H "Authorization: Bearer 12345678-9abc-defg-hijk-lmnopqrs"

import requests

url = "https://restapi.actonsoftware.com/api/1/list/l-ctx"

payload = {}
headers = {
  'Authorization': 'Bearer 12345678-9abc-defg-hijk-lmnopqrs'
}

response = requests.request("GET", url, headers=headers, data = payload)

print(response.text.encode('utf8'))

package com.acton.api.client.endpoint;

import com.mashape.unirest.http.HttpResponse;
import com.mashape.unirest.http.JsonNode;
import com.mashape.unirest.http.Unirest;
import com.mashape.unirest.http.exceptions.UnirestException;
import org.json.JSONArray;

public class GetListByIDExample 
	{
	static String BASE_URL 		= "https://restapi.actonsoftware.com/";
	static String ACTON_USERNAME 	= "{your username}";
	static String ACTON_PASSWORD 	= "{your password}";
	static String CLIENT_ID 	= "{your client id/key}";
	static String CLIENT_SECRET 	= "{your client secret}";

	public static void main(String[] args) 
		{
		try 	{
			String access_token = getAccessToken();
			Unirest.setDefaultHeader("Authorization", "Bearer " + access_token);
			printListHeaders(); 
        		} 
		catch (UnirestException e) 
			{
			e.printStackTrace();
        		}
    		}

	/**
	  * This method uses Download a List endpoint 
	  * and prints all the headers of the List
	  */

	private static void printListHeaders() throws UnirestException 
		{
		// Get the list with id "l-ctx"
		HttpResponse listResponse = Unirest.get(BASE_URL + "/api/1/list/l-ctx").asJson();
		// Get headers as array
		JSONArray headers =listResponse.getBody().getObject().getJSONArray("headers");
		// Iterate thorough all the headers and print
		for (int i=0;i<headers.length();i++)
			System.out.println(headers.getString(i));
    		}

	/**
	  * This is an util method to get access token
          */

	private static String getAccessToken() throws UnirestException 
		{
		// POST to token url with password grant_type to get token.

		HttpResponse jsonResponse = Unirest.post(BASE_URL + "token")
			.header("accept", "application/json")
			.field("grant_type", "password")
			.field("username", ACTON_USERNAME)
			.field("password", ACTON_PASSWORD)
			.field("client_id", CLIENT_ID)
			.field("client_secret", CLIENT_SECRET)
			.asJson();
		// Strip access_token from response and return it.
		return jsonResponse.getBody().getObject().getString("access_token");
    		}
	}