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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_access_token(self, refresh_token):
 """ Use a refresh token to obtain a new access token """


        token = requests.post(GOOGLE_OAUTH2_TOKEN_URL, data=dict(
            refresh_token=refresh_token,
            grant_type='refresh_token',
            client_id=self.client_id,
            client_secret=self.client_secret,
        )).json()

        if not token or token.get('error'):
            return

        return token