# Environment Variables * Environment variables allow developers to switch between DEV and PROD for example * It allows for definition of different variables based on needs * Allows to define variables dynamically #### To define Environment variables such as the URL:

* After this has been defined, you can call it in the operation path:

#### It also became harder to test our API since we have added the login logic and protected routes * So to save some time, we can automate the definition of the JWT as an environment variable through code * This should be done under the `login` path operation as to define it directly as you log in * Navigate to the `Tests` tab and select `Set an environment variable` * Use the following code to set it dynamically ```python pm.environment.set("JWT", pm.response.json().access_token); ``` * The above code sets the environment variable as `JWT` with the value fetching first the response, then transforming it into a JSON output from which the variable named in the return output is called * In our case `access_token` but can be anything as it's app defined under the route return

* After this is defined, we can call it under the authorization tab as `{{JWT}}` to always have it update on login

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