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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 _build_url(self, endpoint):
 """ Returns a fully qualified URL """

        server = None
        if "://" in endpoint:
            # looks like an url, let's break it down
            server, endpoint = self._deconstruct_url(endpoint)

        endpoint = endpoint.lstrip("/")
        url = "{proto}://{server}/{endpoint}".format(
            proto=self.protocol,
            server=self.client.server if server is None else server,
            endpoint=endpoint,
        )
        return url