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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(config, schema=CLUSTER_CONFIG_SCHEMA):
 """Required Dicts indicate that no extra fields can be introduced."""

    if not isinstance(config, dict):
        raise ValueError("Config {} is not a dictionary".format(config))

    check_required(config, schema)
    check_extraneous(config, schema)