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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 supported_providers(self):
 """ Request a list of all available providers :returns: A list of all available providers (e.g. {'provider': 'ec2_ap_northeast', 'title': 'EC2 AP NORTHEAST'}) """

        req = self.request(self.uri + '/providers', api_version=2)
        providers = req.get().json()
        supported_providers = providers['supported_providers']
        return supported_providers