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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 _convert_connected_app(self):
 """Convert Connected App to service"""

        if self.services and "connected_app" in self.services:
            # already a service
            return
        connected_app = self.get_connected_app()
        if not connected_app:
            # not configured
            return
        self.logger.warning(
            "Reading Connected App info from deprecated config."
            " Connected App should be changed to a service."
            " If using environment keychain, update the environment variable."
            " Otherwise, it has been handled automatically and you should not"
            " see this message again."
        )
        ca_config = ServiceConfig(
            {
                "callback_url": connected_app.callback_url,
                "client_id": connected_app.client_id,
                "client_secret": connected_app.client_secret,
            }
        )
        self.set_service("connected_app", ca_config)