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Click on the Create New App and you would be redirected to the application creation page.
Enter your application details and click Create your Twitter application.
Into the Keys and Access Tokens tab you can find Consumer Key (API Key), Consumer Secret (API Secret) and other Application Settings.
Under the Your Access Token section, click on Create my access token. Now you can see the Access Token details under the Your Access Token section.
Select that API Key and API Secret and enter Configuration of Twitter to finish.
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