Tutorial: Send Transactional Emails via Mailgun API Using a Python CLI

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A developer tutorial on DEV Community walks through building a small Python command-line tool that sends transactional emails using Mailgun's HTTP API, eliminating the need for a dedicated mail server. The CLI supports four actions: sending an email, listing sent messages, checking delivery status, and deleting a record. The project is structured across four files, with the core Mailgun logic handled in a dedicated client module and sent email data stored locally in a JSON file. The guide covers Mailgun account setup, sandbox domain restrictions, and secure credential management via environment variables. A key warning highlights that sandbox domains only deliver to pre-authorized recipients, and undelivered emails are silently accepted by the API — making the built-in status-check feature especially useful.

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