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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 read_config(self):
 """ Read config from a file. Invalid config values will be discarded and defaults used in their place. """

        _config = self.config["dikicli"]
        # TODO: what if file doesn't exist?
        if self.config_file.is_file():
            logger.debug("Reading config file: %s", self.config_file.as_posix())
            with open(self.config_file, mode="r") as f:
                self.config.read_file(f)

            # DIKI_DATA_DIR should always take precedence if it's set
            if "DIKI_DATA_DIR" in os.environ:
                _config["data dir"] = DATA_DIR.as_posix()

            w = _config.get("linewrap")
            try:
                w = int(w)
                if w < 0:
                    raise ValueError()
            except ValueError:
                logger.warning("Config: Invalid linewrap value. Using default.")
                _config["linewrap"] = self.default_config["linewrap"]

            c = _config.get("colors")
            if c.lower() not in ["yes", "no", "true", "false"]:
                logger.warning("Config: Invalid colors value. Using default.")
                _config["colors"] = self.default_config["colors"]