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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 _generate_bearer_token(consumer_key, consumer_secret):
 """ Return the bearer token for a given pair of consumer key and secret values. """

    data = [('grant_type', 'client_credentials')]
    resp = requests.post(OAUTH_ENDPOINT,
                         data=data,
                         auth=(consumer_key, consumer_secret))
    logger.warning("Grabbing bearer token from OAUTH")
    if resp.status_code >= 400:
        logger.error(resp.text)
        resp.raise_for_status()

    return resp.json()['access_token']