Download just the first chunk of an mp4 file to test that the url contains something.

download_fist_chunk_mp4.py

import requests

# From https://stackoverflow.com/a/28374584
def downloadfile(name,url):
    name=name+".mp4"
    r=requests.get(url)
    print("****Connected****")
    f=open(name,'wb');
    print("Downloading.....")
    for chunk in r.iter_content(chunk_size=255):
        if chunk: # filter out keep-alive new chunks
            f.write(chunk)
    print("Done")
    f.close()

def download_file_first_chunk(name,url):
    name=name+".mp4"
    r=requests.get(url)
    print("****Connected****")
    f=open(name,'wb');
    print("Downloading.....")
    for chunk in r.iter_content(chunk_size=255):
        if chunk: # filter out keep-alive new chunks
            f.write(chunk)
            break
    print("Done")
    f.close()

#Test downloading a single mp4 file (this file was randomly selected from 3speak)
downloadfile("Test_One", "https://threespeakvideo.b-cdn.net/qnofhybs/NDSQFvtUiifagTtvdZeaCQFdgbLHZrGKzhuzjUlspEAXrOVUHXgWsLzJHDZaaUZH.mp4")
download_file_first_chunk("Test_One_first_chunk", "https://threespeakvideo.b-cdn.net/qnofhybs/NDSQFvtUiifagTtvdZeaCQFdgbLHZrGKzhuzjUlspEAXrOVUHXgWsLzJHDZaaUZH.mp4")