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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 Refresh(self):
 """Uses the Refresh Token to retrieve and set a new Access Token. Raises: google.auth.exceptions.RefreshError: If the refresh fails. """

    with requests.Session() as session:
      session.proxies = self.proxy_config.proxies
      session.verify = not self.proxy_config.disable_certificate_validation
      session.cert = self.proxy_config.cafile

      self.creds.refresh(
          google.auth.transport.requests.Request(session=session))