Let's say something like this is being returned.

HTTPSConnectionPool(host='foo.example.com', port=443): 
Max retries exceeded with url: /api/v1/bar 
(Caused by SSLError(SSLError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:877)'),))

I typically happen upon this when using requests to submit a GET or POST or PATCH request to an API. This should only happen when targetting an API using a secure protocol such as HTTPS, perhaps like this.

#!/usr/bin/python
import requests

try:
  response = requests.post(
    "https://foo.example.com/api/v1/bar", 
    headers={ "Content-Type": "application/json" },
    data={ "hello": "world" }
  )
except Exception as exception:
  print(exception)
else:
  print("requests.post appears to have been successful")

If the API is trusted, such as when submitting the request to an API in your private network, I typically just add verify=False to the GET or POST or PATCH request.

#!/usr/bin/python
import requests

requests.post(
    "https://foo.example.com/api/v1/bar", 
    headers={ "Content-Type": "application/json" },
    data={ "hello": "world" },
    verify=False
)