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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 validate_config(cls, config):
 """ Validates that a config file path and a control socket file path and pid file path are all present in the HAProxy config. """

        if "config_file" not in config:
            raise ValueError("No config file path given")
        if "socket_file" not in config:
            raise ValueError("No control socket path given")
        if "pid_file" not in config:
            raise ValueError("No PID file path given")
        if "stats" in config and "port" not in config["stats"]:
            raise ValueError("Stats interface defined, but no port given")
        if "proxies" in config:
            cls.validate_proxies_config(config["proxies"])

        return config