Receiving 400 bad request from AWS Lambda

Using the dashboard API I have a request that works perfectly in postman but I’m having trouble getting any results when sending from and AWS Lambda Function. 

When I use the below code I get “HTTP 400: Bad Request (Unable to create definition from arguments)”

    event_dict = str({"event_type":"Activate%20Lesson"})
    url = f"https://amplitude.com/api/2/events/segmentation?e={event_dict}&start=20201201&end=20201231&i=1"
    
    payload=''
    headers = urllib3.make_headers(basic_auth='XXXXXXXXXXXXX:XXXXXXXXXXXXX')

    response = http.request('GET',
                        url,
                        body = payload,
                        headers = headers,
                        retries = False)

    res_data = response.data
    print(headers)
    print(res_data)
    print(url)
    return res_data
 

When I use below code I get an empty response:

    event_dict = str({"event_type":"Activate%20Lesson"})
    url = f"https://amplitude.com/api/2/events/segmentation?e={event_dict}&start=20201201&end=20201231&i=1"
    
    payload=''headers = {'Authentication' : 'Basic XXXXXXXXXXXXXXX:XXXXXXXXXXXXXX’}

    response = http.request('GET',
                        url,
                        body = payload,
                        headers = headers,
                        retries = False)

    res_data = response.data
    print(headers)
    print(res_data)
    print(url)
    return res_data

Again, when I test this endpoint in Postman I’m getting the JSON  response as expected. I could use some input on troubleshooting.