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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 authenticate(self, username=None, password=None, api_key=None, tenant_id=None, connect=False):
 """ If the user's credentials include an API key, the default behavior will work. But if they are using a password, the initial attempt will fail, so try again, but this time using the standard password format. The 'connect' parameter is retained for backwards compatibility. It no longer has any effect. """

        try:
            super(RaxIdentity, self).authenticate(username=username,
                    password=password, api_key=api_key, tenant_id=tenant_id)
        except exc.AuthenticationFailed:
            self._creds_style = "password"
            super(RaxIdentity, self).authenticate(username=username,
                    password=password, api_key=api_key, tenant_id=tenant_id)