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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 valid_config_exists(config_path=CONFIG_PATH):
 """Verify that a valid config file exists. Args: config_path (str):
 Path to the config file. Returns: boolean: True if there is a valid config file, false if not. """

    if os.path.isfile(config_path):
        try:
            config = read_config(config_path)
            check_config(config)
        except (ConfigurationError, IOError):
            return False
    else:
        return False
    return True