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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 _verify_client(self, low):
        '''
        Verify that the client is in fact one we have
        '''
        if 'client' not in low or low.get('client') not in self.saltclients:
            self.set_status(400)
            self.write("400 Invalid Client: Client not found in salt clients")
            self.finish()
            return False
        return True