API key permissions mention in USAGE.md (sendgrid#821)

int-ua · thinkingserious · commit 021a9dc7dd2a · 2019-09-11T08:47:03.000-07:00
diff --git a/USAGE.md b/USAGE.md
@@ -2,6 +2,8 @@ This documentation is based on our [OAI specification](https://github.com/sendgr
 
 # INITIALIZATION
 
+Make sure your API key has the [required permissions](https://sendgrid.com/docs/ui/account-and-settings/api-keys/).
+
 ```python
 from sendgrid import SendGridAPIClient
 import os
