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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 list_projects(self):
 """ Lists all deployed projects. First class, maps to Scrapyd's list projects endpoint. """

        url = self._build_url(constants.LIST_PROJECTS_ENDPOINT)
        json = self.client.get(url, timeout=self.timeout)
        return json['projects']