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1. Click on POST /signIn button under the Auth category.
2. Click the Try it out button (RHS). The "User info for signIn" fields should show up.
3. Click the Edit button. The field should now become editable.
4. Fill out your account credentials.
5. Click the blue Execute button.
6. If successful, you should receive an HTTP 200 response back with JSON data. If there was a form error, you should receive an HTTP 4XX response back with an appropriate error message.
7. Select and copy the token JSON string into the clipboard
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