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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def get_credentials(cls, consumer_key, code):
        '''
        Fetches access token from using the request token and consumer key

        '''
        headers = {
            'X-Accept': 'application/json',
        }
        url = 'https://getpocket.com/v3/oauth/authorize'
        payload = {
            'consumer_key': consumer_key,
            'code': code,
        }

        return cls._make_request(url, payload, headers)[0]