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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 make_secure_stub(credentials, user_agent, stub_class, host, extra_options=()):
 """Makes a secure stub for an RPC service. Uses / depends on gRPC. :type credentials: :class:`google.auth.credentials.Credentials` :param credentials: The OAuth2 Credentials to use for creating access tokens. :type user_agent: str :param user_agent: The user agent to be used with API requests. :type stub_class: type :param stub_class: A gRPC stub type for a given service. :type host: str :param host: The host for the service. :type extra_options: tuple :param extra_options: (Optional) Extra gRPC options passed when creating the channel. :rtype: object, instance of ``stub_class`` :returns: The stub object used to make gRPC requests to a given API. """

    channel = make_secure_channel(
        credentials, user_agent, host, extra_options=extra_options
    )
    return stub_class(channel)